David A. Spain, MD

Ned and Carol Spieker Endowed Professor

Surgery - General Surgery

Bio

Bio

Dr. David A. Spain is the David L. Gregg, MD Professor and Chief of Acute Care Surgery. His clinical areas of specialty are emergency and elective general surgery, trauma and critical care. His research focus is assessment of clinical care, systems of care and introduction of new technology. He is the current Recorder and Program Chair of the American Association for the Surgery of Trauma and a Governor of the American College of Surgeons. He is the editor of the new textbook Scientific American's Critical Care of the Surgical Patient.

Research & Scholarship

Current Research and Scholarly Interests

Our main areas of interest are clinical research in shock, sepsis, multiple organ faliure and ICU pneumonia, as well as organizational characteristic of well functioning trauma centers and systems. We are also developing a program in Health Services Research focused on access to specialized, high acuity care

Clinical Trials

Sigh Ventilation to Increase Ventilator-Free Days in Victims of Trauma at Risk for Acute Respiratory Distress SyndromeNot Recruiting

A randomized, concurrent controlled trial to assess if adding sigh breaths to usual invasive
mechanical ventilation of victims of trauma who are at risk of developing ARDS will decrease
the number of days they require invasive mechanical ventilation.

Abstract

Florida serves as a model for the study of trauma system performance. Between 2010 and 2104, 5 new trauma centers were opened alongside 20 existing centers. The purpose of this study was to explore the impact of trauma system expansion on system triage performance and trauma center patients' profiles.A statewide data set was queried for all injury-related discharges from adult acute care hospitals using International Classification of Diseases, Ninth Revision (ICD-9) codes for 2010 and 2014. The data set, inclusion criteria, and definitions of high-risk injury were chosen to match those used by the Florida Department of Health in its trauma registry. Hospitals were classified as existing Level I (E1) or Level II (E2) trauma centers and new E2 (N2) centers.Five N2 centers were established 11.6 to 85.3 miles from existing centers. Field and overall trauma system triage of high-risk patients was less accurate with increased overtriage and no change in undertriage. Annual volume at N2 centers increased but did not change at E1 and E2 centers. In 2014, Patients at E1 and E2 centers were slightly older and less severely injured, while those at N2 centers were substantially younger and more severely injured than in 2010. The injured patient-payer mix changed with a decrease in self-pay and commercial patients and an increase in government-sponsored patients at E1 and E2 centers and an increase in self-pay and commercial patients with a decrease in government-sponsored patients at N2 centers.Designation of new trauma centers in a mature system was associated with a change in established trauma center demographics and economics without an improvement in trauma system triage performance. These findings suggest that the health of an entire trauma system network must be considered in the design and implementation of a regional trauma system.Therapeutic/care management study, level IV; epidemiological, level IV.

Abstract

To quantify the inflation-adjusted costs associated with initial hospitalizations for firearm-related injuries in the United States.We used the Healthcare Cost and Utilization Project Nationwide Inpatient Sample to identify patients admitted for firearm-related injuries from 2006 to 2014. We converted charges from hospitalization to costs, which we inflation-adjusted to 2014 dollars. We used survey weights to create national estimates.Costs for the initial inpatient hospitalization totaled $6.61 billion. The largest proportion was for patients with governmental insurance coverage, totaling $2.70 billion (40.8%) and was divided between Medicaid ($2.30 billion) and Medicare ($0.40 billion). Self-pay individuals accounted for $1.56 billion (23.6%) in costs.From 2006 to 2014, the cost of initial hospitalizations for firearm-related injuries averaged $734.6 million per year. Medicaid paid one third and self-pay patients one quarter of the financial burden. These figures substantially underestimate true health care costs. Public health implications. Firearm-related injuries are costly to the US health care system and are particularly burdensome to government insurance and the self-paying poor.

Abstract

Trauma-related deaths remain an important public health problem. One group susceptible to death due to traumatic mechanisms is U.S. Law Enforcement (LE). We hypothesized that LE officers experienced a higher chance of violent death compared to the general U.S. population and that risks have increased over time.The National Institute on Occupational Safety and Health (NIOSH) National Occupational Mortality Surveillance (NOMS) is a population-based survey of occupational deaths. It includes data for workers who died during 1985-1998 in one of 30 U.S states (EARLY period). Additional deaths were added from 23 U.S. states in 1999, 2003-2004, 2007-2010 (LATE period). Mortality rates are estimated by calculating proportionate mortality ratios (PMR). A PMR above 100 is considered to exceed the average background risk for all occupations. All adults >18 years of age whose primary occupation was listed as "Law Enforcement Worker" were included in the analysis.Law enforcement personnel were more likely to die from an injury compared to the general population (Figure 1). The overall PMR for injury in EARLY was 111 (95% Confidence Interval [CI] 108-114, p<0.01), and for LATE was 118 (95% CI 110-127, p<0.01). Four mechanisms of death reached statistical significance: motor vehicle traffic (MVT)-driver, MVT-other, intentional self-harm, and assault/homicide. The highest PMR in EARLY was associated with firearms (PMR 272, 95% CI 207-350, p<0.01). The highest PMR in LATE was associated with death due to being a driver in an MVT (PMR 194, 95% CI 169-222, p<0.01). There were differences in risk of death by race and gender. White females had the highest PMR due to Assault and Homicide (PMR 317, 95% CI 164-554, p<0.01). All groups had similar risks of death due to Intentional Self-Harm (PMR 130-171).The risk of death for US LEOs is high and increasing over time, suggesting an at-risk population that requires further interventions. Targeted efforts based on risk factors, such as gender and race, may assist with the development of prevention programs for this population.

Abstract

In 2015, the American College of Surgeons Committee on Trauma convened a consensus conference to develop the Needs-Based Assessment of Trauma Systems (NBATS) tool to assist in determining the number of trauma centers required for a region. We tested the performance of NBATS with respect to the optimal number of trauma centers needed by region in California.Trauma center data were obtained from the California Emergency Services Authority Information Systems (CEMSIS). Numbers of admitted trauma patients (ISS > 15) were obtained using statewide nonpublic admissions data from the California Office of Statewide Health Planning and Development (OSHPD), CEMSIS, and data from local emergency medical service agency (LEMSA) directors who agreed to participate in a telephone survey. Population estimates per county for 2014 were obtained from the U.S. Census. NBATS criteria used included population, transport time, community support, and number of discharges for severely injured patients (ISS > 15) at nontrauma centers and trauma centers. Estimates for the number of trauma centers per region were created for each of the three data sources and compared to the number of existing centers.A total of 62 state-designated trauma centers were identified for California: 13 (21%) Level I, 36 (58%) Level II, and 13 (11%) Level III. NBATS estimates for the total number of trauma centers in California were 27% to 47% lower compared to the number of trauma centers in existence, but this varied based on urban/rural status. NBATS estimates were lower than the current state in 70% of urban areas but were higher in almost 90% of rural areas. All data sources (OSHPD, CEMSIS, local data) produced similar results.Estimates from the NBATS tool are different from what is currently in existence in California, and differences exist based on whether the region is rural or urban. Findings from the current study can help inform future iterations of the NBATS tool.Economic, level V.

Abstract

Acute-care surgery (ACS), trauma, and surgical critical care (SCC) fellowships graduate fellows deemed qualified to perform complex cases immediately upon graduation. We hypothesize international fellow rotations can be a resource to supplement operative case exposure.A survey was sent to all program directors (PDs) of ACS and SCC fellowships via e-mail. Data were captured and analyzed using the REDCap (Research Electronic Data Capture) tool.The survey was sent to 113 PDs, with a response rate of 42%. Most fellows performed less than 150 operative cases (59.5%). The majority of PDs thought the operative exposure either could be improved or was not enough to ensure expertise in trauma and emergent general surgery. Only a minority of the PDs found their case load exceptional (can be improved: 43%, not enough: 30% exceptional: 27%). Most PDs thought an international experience could supplement the breadth of cases, provide research opportunities, and improve understanding of trauma systems (70%). Ten sites offered international rotations (70%). Most fellowships would be willing to provide reciprocity to the host institution (90%).The majority of PDs for ACS, trauma, and SCC programs perceive a need for increased quality and quantity of operative cases. The majority recognize international fellow rotations as a valuable tool to supplement fellows' education.

Abstract

Trauma patients with vascular injuries have historically been within a general surgeon's operative ability. Changes in training and decline in operative trauma have decreased trainees' exposure to these injuries. We sought to determine how frequently vascular procedures are performed at US trauma centers to quantify the need for general surgeons trained to manage vascular injuries.We conducted a retrospective analysis of the National Trauma Data Base (NTDB) from 2012 compared with 2002. Patients with general surgical and vascular procedures were identified using International Classification of Diseases, Ninth Revision, procedure codes 38.0-39.99, excluding 38.9-38.99.General surgery or vascular operations were performed on 12,099 (24%) of 50,248 severely injured adult patients in 2002 and 21,854 (16%) of 138,009 injured patients in 2012. Nineteen percent to 26% of all patients underwent vascular procedures. Patients with combined general surgery and vascular procedures were less likely to be discharged home and more likely to die. In 2002, 6% of severely injured adult trauma patients underwent open vascular procedures at level III/IV trauma centers; by 2012, only 1% of vascular surgery procedures were performed at level III/IV centers (P

Abstract

Bleeding from pelvic fractures can be lethal. Angioembolization (AE) and external fixation (EXFIX) are common treatments to control bleeding, but it is not known how frequently they are used. We hypothesized that AE would be increasingly more common compared with EXFIX over time.The National Trauma Data Bank for the years from 2008-2010 were used. Patients were included in the study if they had an International Classification of Diseases, ninth edition, Clinical Modification codes for pelvic fractures and were aged ≥18 y. Patients were excluded if they had isolated acetabular fractures, were not admitted, or had minor injuries. Outcomes included receiving a procedure and in-hospital mortality.A total of 22,568 patients met study criteria. AE and EXFIX were performed in 746 (3.3%) and 663 (2.9%) patients, respectively. AE was performed more often as the study period progressed (2.5% in 2007 to 3.7% in 2010; P

Abstract

The target rate for trauma undertriage is <5 per cent, but rates are as high as 30 to 40 per cent in many trauma systems. We hypothesized that high undertriage rates were due to the tendency to undertriage injured elderly patients and a growing elderly population. We conducted a retrospective analysis of all hospital visits in California using the Office of Statewide Health Planning and Development Database over a 5-year period. All hospital admissions and emergency department visits associated with injury were longitudinally linked. The primary outcome was triage pattern. Triage patterns were stratified across three dimensions: age, mechanism of injury, and access to care. A total of 60,182 severely injured patients were included in the analysis. Fall-related injuries were frequently undertriaged compared with injuries from motor vehicle collisions (MVCs) and penetrating trauma (52% vs 12% and 10%, respectively). This pattern was true for all age groups. Conversely, MVCs and penetrating traumas were associated with high rates of overtriage (>70% for both). In conclusion, in contrast to our hypothesis, we found that triage is largely determined by mechanism of injury regardless of injury severity. High rates of undertriage are largely due to the undertriage of fall-related injuries, which occurs in both younger and older adults. Patients injured after MVCs and penetrating trauma victims are brought to trauma centers regardless of injury severity, resulting in high rates of overtriage. These findings suggest an opportunity to improve trauma system performance.

Abstract

Trauma center care has been associated with improved mortality. It is not known if access to trauma center care is also associated with reduced readmissions. We hypothesized that receiving treatment at a trauma center would be associated with improved care and therefore would be associated with reduced readmission rates.We conducted a retrospective analysis of all hospital visits in California using the Office of Statewide Health Planning and Development Database from 2007-2008. All hospital admissions and emergency department visits associated with injury were longitudinally linked. Regions were categorized by whether or not they had trauma centers. We excluded all patients younger than 18 years of age. We performed univariate and multivariate regression analyses to determine if readmissions were associated with patient characteristics, length of stay for initial hospitalization, trauma center access, and triage patterns.A total of 211,504 patients were included in the analysis. Of these, 5,094 (2%) died during the index hospitalization. Of those who survived their initial hospitalization, 79,123 (38%) experienced one or more readmissions to any hospital within one year. The majority of these were one-time readmissions (62%) but 38% experienced multiple readmissions. Over 67% of readmissions were unplanned and 8% of readmissions were for a trauma. After controlling for patient variables known to be associated with readmissions, primary triage to a trauma center was associated with a lower odds of readmission (OR 0.89, p<0.001). The effect of transport to a trauma center remained significantly associated with decreased odds of readmission at one year (OR 0.96, p<0.001).Readmissions after injury are common and are often unscheduled. While patient factors play a role in this, care at a trauma center is also associated with decreased odds for re-admission, even when controlling for severity of injury. This suggests that the benefits of trauma center care extend beyond improvements in mortality to improved long-term outcomes.Economic/Decision LEVEL OF EVIDENCE: Level IV.

Uninsured status may be more predictive of outcomes among the severely injured than minority raceINJURY-INTERNATIONAL JOURNAL OF THE CARE OF THE INJUREDGerry, J. M., Weiser, T. G., Spain, D. A., Staudenmayer, K. L.2016; 47 (1): 197-202

Abstract

Worse outcomes in trauma in the United States have been reported for both the uninsured and minority race. We sought to determine whether disparities would persist among severely injured patients treated at trauma centres where standard triage trauma protocols limit bias from health systems and providers.We performed a retrospective analysis of the 2010-2012 National Sample Program from the National Trauma Databank, which is a nationally representative sample of trauma centre performance in the United States. The database was screened for adults ages 18-64 who had a known insurance status. Outcomes measured were in-hospital mortality and post-hospital care.There were 739,149 injured patients included in the analysis. Twenty-eight percent were uninsured, and 34 percent were of minority race. In the adjusted analysis, uninsured status (OR 1.60, 1.29-1.98, p<0.001) and black race (OR 1.24, 1.04-1.49, p=0.019) were significant predictors of mortality. Only uninsured status was a significant negative predictor of post-hospital care (OR 0.43, 0.36-0.51, p<0.001). As injury severity increased, only insurance status was a significant predictor of both increased mortality (OR 1.68, 1.29-2.19, p<0.001) and decreased post-hospital care (OR 0.45, 0.32-0.63, p<0.001).Uninsured status is independently associated with higher in-hospital mortality and decreased post-hospital care in patients with severe injuries in a nationally representative sample of trauma centres in the United States. Increased in-hospital mortality is likely due to endogenous patient factors while decreased post-hospital care is likely due to economic constraints. Minority race is less of a factor influencing disparate outcomes among the severely injured.

Abstract

The initial goal of evaluating a patient with SBO is to immediately identify strangulation and need for urgent operative intervention, concurrent with rapid resuscitation. This relies on a combination of traditional clinical signs and CT findings. In patients without signs of strangulation, a protocol for administration of Gastrografin immediately in the emergency department efficiently sorts patients into those who will resolve their obstructions and those who will fail nonoperative management.Furthermore, because of the unique ability of Gastrografin to draw water into the bowel lumen, it expedites resolution of partial obstructions, shortening time to removal of nasogastric tube liberalization of diet, and discharge from the hospital. Implementation of such a protocol is a complex, multidisciplinary, and time-consuming endeavor. As such, we cannot over emphasize the importance of clear, open communication with everyone involved.If surgical management is warranted, we encourage an initial laparoscopic approach with open access. Even if this results in immediate conversion to laparotomy after assessment of the intra-abdominal status, we encourage this approach with a goal of 30% conversion rate or higher. This will attest that patients will have been given the highest likelihood of a successful laparoscopic LOA.

Abstract

Spine trauma patients may represent a group for whom insurance fails to provide protection from catastrophic medical expenses, resulting in the transfer of financial burden onto individual families and public payers. This study compares the rate of insurance discontinuation for patients who underwent surgery for traumatic spine injury with and without spinal cord injury with the rate for matched control subjects.We used the MarketScan database to perform a retrospective cohort study of privately insured spine trauma patients who underwent surgery from 2006 to 2010. Kaplan-Meier survival analysis was used to assess the time to insurance discontinuation. Cox proportional-hazards regression was used to determine hazard ratios for insurance discontinuation among spine trauma patients compared with the matched control population.The median duration of existing insurance coverage was 20.2 months for those with traumatic spinal cord injury, 25.6 months for those with traumatic spine injury without spinal cord injury, and 48.0 months for the matched control cohort (log-rank p < 0.0001). After controlling for multiple covariates, the hazard ratios for discontinuation of insurance were 2.02 (95% CI [confidence interval], 1.83 to 2.23) and 2.78 (95% CI, 2.31 to 3.35) for the trauma patients without and with spinal cord injury, respectively, compared with matched controls.Rates of insurance discontinuation are significantly higher for trauma patients with severe spine injury compared with the uninjured population, indicating that patients with disabling injuries are at increased risk for loss of insurance coverage.

Abstract

Patients with mild traumatic brain injury (TBI) as defined by an admission Glasgow Coma Score (GCS) of 14-15 often do not require neurosurgical interventions, but which patients will go on to require neurosurgical care has been difficult to predict. We hypothesized that injury patterns would be associated with need for eventual neurosurgical intervention in mild TBI.The National Trauma Databank (2007-2012) was queried for patients with blunt injury and a diagnosis of TBI with an emergency department GCS of 14-15. Patients were stratified by age and injury type. Multiple logistic regression for neurosurgical intervention was run with patient demographics, physiologic variables, and injury diagnoses as dependent variables.The study included 50,496 patients, with an overall 8.8 % rate of neurosurgical intervention. Neurosurgical intervention rates varied markedly according to injury type, and were only correlated with age for patients with epidural and subdural hemorrhage. In multiple logistic regression, TBI diagnoses were predictive of need for neurosurgical interventions; moreover, after controlling for injury type and severity score, age was not significantly associated with requiring neurosurgical intervention.We found that in mild TBI, injury pattern is associated with eventual need for neurosurgical intervention. Patients with cerebral contusion or subarachnoid hemorrhage are much less likely to require neurosurgical intervention, and the effects of age are not significant after controlling for other patient factors. Prospective studies should validate this finding so that treatment guidelines can be updated to better allocate ICU resources.

Abstract

Due to the scarcity of specialized resources for pediatric trauma, "regionalization," or a system designed to get "the right child, to the right place, at the right time," is vital to quality pediatric trauma care. In Northern California, four pediatric trauma centers serve 3.9 million children within a geographically diverse area of 113,630 square miles. A significant proportion of children with trauma is initially triaged to nontrauma hospitals and may require subsequent transfer to a specialty center. Trauma transfer patterns to a pediatric trauma center may provide insight into regional primary triage practices. Transfers from hospitals in close proximity to pediatric trauma centers might suggest that some children could have avoided transfer with minimal additional transport time. While pediatric trauma centers are scarce and serve as regional resources, transfers from beyond the regular catchment area of a trauma center could be an indication of clinical need.The objective of this study was to gain an understanding of patterns of pediatric trauma transfer to all pediatric trauma centers within the region as a first step in assessing the efficacy and efficiency of trauma triage. The authors examined three groups of transfer patients: transfers from within the same county as the pediatric trauma center (near transfers), transfers from counties adjacent to the pediatric trauma center (catchment transfers), and transfers from more distant counties (far transfers). The hypothesis was that catchment transfers would form the bulk of transfers, near transfers would compose < 10% of total transfers, and far transfers would be younger and more severely injured than catchment transfers.This was a retrospective analysis of institutional trauma registry data of children < 18 years from all pediatric trauma centers in Northern California from 2001 through 2009. Transfers were characterized by the location of the transfer hospital relative to the location of the pediatric trauma center. Characteristics associated with near transfer compared to primary triage to a pediatric trauma center were identified, as well as characteristics associated with far transfer compared to catchment transfer.A total of 2,852 of 11,952 (23.9%) pediatric trauma patients were transfers. Near transfers comprised 24.5% of cases, catchment transfers were 37.4%, and far transfers were 38.2%. After controlling for demographic, clinical, and geographic factors, younger age, higher Injury Severity Score (ISS), public versus private insurance, and an injury mechanism of "fall" were associated with near transfer rather than direct triage. Older age, higher ISS, and mechanism of "motor vehicle crash" were associated with far rather than catchment transfer.This analysis of patterns of transfer to all pediatric trauma centers within Northern California gives the most comprehensive population view of pediatric trauma triage to date, to the authors' knowledge. Trauma transfers comprise an important minority of patients cared for at pediatric trauma centers. The number of near transfers documented indicates the potential to improve the primary triage process of patients to pediatric trauma centers. The frequency of far transfers substantiates the well-known shortage of pediatric trauma expertise. Development of regionwide standardized transfer protocols and agreements between hospitals, as well as standardized monitoring of the process and outcomes, could increase efficiency of care.

Abstract

Clostridium ramosum is a common enteric anaerobe but infrequently also a cause of pathologic infection.Case report and literature review.We reviewed 12 case reports describing infection with C. ramosum. When pathogenic, C. ramosum is cultured most commonly from the inner ear, anaerobic blood samples, or abscesses. Patients with such infections fall into two demographic groups, consisting of young children with ear infections or immunocompromised adults with bacteremia. Resistance of C. ramosum to antibiotics is uncommon.Clostridium ramosum is a common but generally commensal bacterial species. Rarely, it becomes pathogenic in young children or immunosuppressed adults.

Abstract

IMPORTANCE Trauma is the leading cause of potential years of life lost before age 65 years in the United States. Timely care in a designated trauma center has been shown to reduce mortality by 25%. However, many severely injured patients are not transferred to trauma centers after initially being seen at non-trauma center emergency departments (EDs). OBJECTIVES To determine patient-level and hospital-level factors associated with the decision to admit rather than transfer severely injured patients who are initially seen at non-trauma center EDs and to ascertain whether insured patients are more likely to be admitted than transferred compared with uninsured patients. DESIGN, SETTING, AND PARTICIPANTS Retrospective analysis of the 2009 Nationwide Emergency Department Sample. We included all ED encounters for major trauma (Injury Severity Score, >15) seen at non-trauma centers in patients aged 18 to 64 years. We excluded ED discharges and ED deaths. We quantified the absolute risk difference between admission vs transfer by insurance status, while adjusting for age, sex, mechanism of injury, Injury Severity Score, weekend admission and month of visit, and urban vs rural status and median household income of the home zip code, as well as annual ED visit volume and teaching status and US region. MAIN OUTCOMES AND MEASURES Inpatient admission vs transfer to another acute care facility. RESULTS In 2009, a total of 4513 observations from 636 non-trauma center EDs were available for analysis, representing a nationally weighted population of 19 312 non-trauma center ED encounters for major trauma. Overall, 54.5% in 2009 were admitted to the non-trauma center. Compared with patients without insurance, the adjusted absolute risk of admission vs transfer was 14.3% (95% CI, 9.2%-19.4%) higher for patients with Medicaid and 11.2% (95% CI, 6.9%-15.4%) higher for patients with private insurance. Other factors associated with admission vs transfer included severe abdominal injuries (risk difference, 15.9%; 95% CI, 9.4%-22.3%), urban teaching hospital vs non-teaching hospital (risk difference, 26.2%; 95% CI, 15.2%-37.2%), and annual ED visit volume (risk difference, 3.4%; 95% CI, 1.6%-5.3% higher for every additional 10 000 annual ED visits). CONCLUSIONS AND RELEVANCE Patients with severe injuries initially evaluated at non-trauma center EDs were less likely to be transferred if insured and were at risk of receiving suboptimal trauma care. Efforts in monitoring and optimizing trauma interhospital transfers and outcomes at the population level are warranted.

Abstract

Timely access to trauma care requires that severely injured patients are ultimately triaged to trauma centers. We sought to determine triage patterns for the injured population within the state of California to determine those factors associated with undertriage.We conducted a retrospective analysis of all hospital visits in California using the Office of Statewide Health Planning and Development Database from January 1, 2005, and December 31, 2009. All visits associated with injury were linked longitudinally. Sixty-day and one-year mortality was determined using vital statistics data. Primary field triage was defined as field triage to a Level I/II trauma center; retriage was defined as initial triage to a non-Level I/II center followed by transfer to a Level I/II. Regions were organized by local emergency medical services agencies. The primary outcomes were triage patterns and mortality.The undertriage rate was 35% (n = 20,988) but was variable across regions (12-87%). Primary field triage ranged from 7% to 77%. Retriage rates not only were overall low (6% of all severely injured patients) but also varied by region (1-38%). In adjusted analysis, factors associated with a lower odds ratio (OR) of primary field triage included the following: age of 55 years or greater (OR, 0.78; p = 0.001), female sex (OR, 0.88; p = 0.014), greater number of comorbidities (OR, 0.92; p < 0.001), and fall mechanism versus motor vehicle collision (OR, 0.54; p < 0.001). One-year mortality was higher for undertriaged patients (25% vs. 16% and 18% for primary field and retriage, respectively, p < 0.001).This is the first study to create a longitudinal database of all emergency department visits, hospitalizations, and long-term mortality for every severely injured patient within an entire state during a 5-year period. Undertriage varied substantially by region and was associated with multiple factors including access to care and patient factors.Epidemiologic study, level III.

Abstract

Epidemiologic trends in trauma-related mortality in the United States require updating and characterization. We hypothesized that during the past decade, there have been changing trends in mortality that are associated with multiple public health and health care-related factors.Multiple sources were queried for the period of 2002 to 2010: the National Trauma Data Bank, the National Centers for Disease Control, the National Highway Traffic Safety Administration, the Nationwide Emergency Department Sample, and the US Census Bureau. The incidence of injury and mortality for motor vehicle traffic (MVT) collisions, firearms, and falls were determined using National Centers for Disease Control data. National Highway Traffic Safety Administration data were used to determine motor vehicle collision information. Injury severity data were derived from the Nationwide Emergency Department Sample and National Trauma Data Bank. Analysis of mortality trends by year was performed using the Cochran-Armitage test for trend. Time-trend multivariable Poisson regression was used to determine risk-adjusted mortality over time.From 2002 to 2010, the total trauma-related mortality decreased by 6% (p < 0.01). However, mortality trends differed by mechanism. There was a 27% decrease in the MVT death rate associated with a 20% decrease in motor vehicle collisions, 19% decrease in the number of occupant injuries per collision, lower injury severity, and improved outcomes at trauma centers. While firearm-related mortality remained relatively unchanged, mortality caused by firearm suicides increased, whereas homicide-associated mortality decreased (p < 0.001 for both). In contrast, fall-related mortality increased by 46% (5.95-8.70, p < 0.01).MVT mortality rates have decreased during the last decade, owing in part to decreases in the number and severity of injuries. Conversely, fall-related mortality is increasing and is projected to exceed both MVT and firearm mortality rates should current trends continue. Trauma systems and injury prevention programs will need to take into account these changing trends to best accommodate the needs of the injured population.Epidemiologic study, level III.

Abstract

Elderly patients are frequently undertriaged. However, the associations between triage patterns and outcomes from a population perspective are unknown. We hypothesized that triage patterns would be associated with differences in outcomes.This is a population-based, retrospective, cohort study of all injured adults aged 55 years or older, from 3 counties in California and 4 in Utah (2006 to 2007). Prehospital data were linked to trauma registry data, state-level discharge data, emergency department records, and death files. The primary outcome was 60-day mortality. Patients treated at trauma centers were compared with those treated at nontrauma centers. Undertriage was defined as an Injury Severity Score (ISS) >15, with transport to a nontrauma center.There were 6,015 patients in the analysis. Patients who were taken to nontrauma centers were, on average, older (79.4 vs 70.7 years, p < 0.001), more often female (68.6% vs 50.2%, p < 0.01), and less often had an ISS >15 (2.2% vs 6.7%, p < 0.01). There were 244 patients with an ISS >15 and the undertriage rate was 32.8% (n = 80). Overall 60-day mortality for patients with an ISS >15 was 17%, with no difference between trauma and nontrauma centers in unadjusted or adjusted analyses. However, the median per-patient costs were $21,000 higher for severely injured patients taken to trauma centers.This is the first population-based analysis of triage patterns and outcomes in the elderly. We have shown high rates of undertriage that are not associated with higher mortality, but are associated with higher costs. Future work should focus on determining how to improve outcomes for this population.

Abstract

To assess the cost-effectiveness of diagnostic laparoscopy, computed tomography (CT), and magnetic resonance imaging (MRI) after indeterminate ultrasonography in pregnant women with suspected appendicitis.A decision-analytic model was developed to simulate appendicitis during pregnancy taking into consideration the health outcomes for both the pregnant women and developing fetuses. Strategies included diagnostic laparoscopy, CT, and MRI. Outcomes included positive appendectomy, negative appendectomy, maternal perioperative complications, preterm delivery, fetal loss, childhood cancer, lifetime costs, discounted life expectancy, and incremental cost-effectiveness ratios.Magnetic resonance imaging is the most cost-effective strategy, costing $6,767 per quality-adjusted life-year gained relative to CT, well below the generally accepted $50,000 per quality-adjusted life-year threshold. In a setting where MRI is unavailable, CT is cost-effective even when considering the increased risk of radiation-associated childhood cancer ($560 per quality-adjusted life-year gained relative to diagnostic laparoscopy). Unless the negative appendectomy rate is less than 1%, imaging of any type is more cost-effective than proceeding directly to diagnostic laparoscopy.Depending on imaging costs and resource availability, both CT and MRI are potentially cost-effective. The risk of radiation-associated childhood cancer from CT has little effect on population-level outcomes or cost-effectiveness but is a concern for individual patients. For pregnant women with suspected appendicitis, an extremely high level of clinical diagnostic certainty must be reached before proceeding to operation without preoperative imaging.

Abstract

STUDY OBJECTIVE: We determine the minimum mortality reduction that helicopter emergency medical services (EMS) should provide relative to ground EMS for the scene transport of trauma victims to offset higher costs, inherent transport risks, and inevitable overtriage of patients with minor injury. METHODS: We developed a decision-analytic model to compare the costs and outcomes of helicopter versus ground EMS transport to a trauma center from a societal perspective during a patient's lifetime. We determined the mortality reduction needed to make helicopter transport cost less than $100,000 and $50,000 per quality-adjusted life-year gained compared with ground EMS. Model inputs were derived from the National Study on the Costs and Outcomes of Trauma, National Trauma Data Bank, Medicare reimbursements, and literature. We assessed robustness with probabilistic sensitivity analyses. RESULTS: Helicopter EMS must provide a minimum of a 17% relative risk reduction in mortality (1.6 lives saved/100 patients with the mean characteristics of the National Study on the Costs and Outcomes of Trauma cohort) to cost less than $100,000 per quality-adjusted life-year gained and a reduction of at least 33% (3.7 lives saved/100 patients) to cost less than $50,000 per quality-adjusted life-year. Helicopter EMS becomes more cost-effective with significant reductions in patients with minor injury who are triaged to air transport or if long-term disability outcomes are improved. CONCLUSION: Helicopter EMS needs to provide at least a 17% mortality reduction or a measurable improvement in long-term disability to compare favorably with other interventions considered cost-effective. Given current evidence, it is not clear that helicopter EMS achieves this mortality or disability reduction. Reducing overtriage of patients with minor injury to helicopter EMS would improve its cost-effectiveness.

Abstract

Traditionally, trauma resuscitation protocols have advocated sequential administration of therapeutic components, beginning with crystalloid solutions infused to replace lost intravascular volume. However, rapid restoration of the components of blood is essential for ensuring adequate tissue perfusion and for preventing acidosis, coagulopathy, and hypothermia, referred to as the 'lethal triad' in trauma settings. The review summarizes practical approaches for transfusion support of patients with massive hemorrhage.Massive transfusion protocols for blood transfusion support are reviewed, including practical considerations from our own. We maintain an inventory of thawed, previously frozen plasma (four units each of blood group O and A), which can be issued immediately for patients in whom the blood type is known. As frozen plasma requires 45 min to thaw, liquid AB plasma (26 day outdate) functions as an excellent alternative, particularly for patients with unknown or blood group B or AB types.Close monitoring of bleeding and coagulation in trauma patients allows goal-directed transfusions to optimize patients' coagulation, reduce exposure to blood products, and to improve patient outcomes. Future studies are needed to understand and demonstrate improved patient outcomes.

Abstract

Ruptured abdominal aortic aneurysm (rAAA) is a critically time-sensitive condition with outcomes dependent on rapid diagnosis and definitive treatment. Emergency department (ED) death reflects the hemodynamic stability of the patient upon arrival and the ability to mobilize resources before hemodynamic stability is lost. The goals of this study were to determine the incidence and predictors of ED death for patients presenting to EDs with rAAAs.Data for patients presenting with International Classification of Disease, 9th Revision, Clinical Modification codes for rAAA from 2006 to 2008 were extracted from discharge data using the Nationwide Emergency Department Sample (NEDS), Healthcare Cost and Utilization Project, and Agency for Healthcare Research and Quality. The NEDS is the largest stratified weighted sample of US hospital-based ED visits with links to inpatient files. We compared those transferred to those admitted and treated. Sample weights were applied to produce nationally representative estimates. Patient and hospital factors associated with transfer were identified using multivariate logistic regression. These factors were then analyzed for a relationship with ED deaths.A total of 18,363 patients were evaluated for rAAAs. Of these, 7% (1201) died in the ED, 6% (1160) were admitted and died without a procedure, 42% (7731) were admitted and died after repair, and 41% (7479) were admitted, treated, and survived. Transfers accounted for 4% (793) of all ED visits for rAAAs. ED death was more likely for patients seen in nonmetropolitan hospitals (12.7%) vs metropolitan nonteaching (7.0%) or metropolitan teaching hospitals (4.5%; P < .0001). Compared with other regions, the West had a higher ED mortality rate (9.6% vs 5.1%-6.9%; P = .0038). On multivariate analysis, ED death was associated with hospital groups exhibiting both high and low transfer rates.ED death remains a significant cause for mortality for rAAAs and varies by hospital type, rural/urban location, and geographic region. Both delays in ED arrival and delays in providing definitive care may contribute to increased ED death rates, suggesting that improved regional systems of care may improve survival after rAAA.

Abstract

It is controversial whether patients at high risk for pulmonary embolism (PE) should receive prophylactic inferior vena cava filters (IVC) filters. This lack of clarity creates the potential for variability and disparities in care. We hypothesized there would be differential use of prophylactic IVC filters for patients at high risk for PE on the basis of insurance status.We performed a retrospective analysis using the National Trauma Databank (2002-2007). We included adult patients at high risk for PE (traumatic brain injury or spinal cord injury) and excluded patients with a diagnosis of deep venous thrombosis (DVT) or PE. Logistic regression was performed to control for confounders and a hierarchical mixed effects model was used to control for center.A prophylactic filter was placed in 3,331 (4.3%) patients in the study cohort. Patients without insurance had an IVC filter placed less often compared with those with any form of insurance (2.7% vs 4.9%, respectively). After adjusting for confounders, we found that patients without insurance were less likely to receive a prophylactic IVC filter, even when we controlled for center (OR 5.3, P < .001).When guidelines lack clarity, unconscious bias has the potential to create a system with different levels of care based on socioeconomic disparities.

Abstract

Reconstruction of abdominal wall defects is a challenging problem. Often, the surgeon is presented with a patient having multiple comorbidities, who has already endured numerous unsuccessful operations, leaving skin and fascia that are attenuated and unreliable. Our study investigated preoperative, intraoperative, and postoperative factors and techniques during abdominal wall reconstruction to determine which variables were associated with poor outcomes.Data were collected on all patients who underwent ventral abdominal hernia repair by 3 senior-level surgeons at our institution during an 8-year period. In all cases, placement of either a synthetic or a biologic mesh was used to provide additional reinforcement of the repair.A total of 106 patients were included. Seventy-nine patients (75%) had preoperative comorbid conditions. Sixty-seven patients developed a postoperative complication (63%). Skin necrosis was the most common complication (n = 21, 19.8%). Other complications included seroma (n = 19, 17.9%), cellulitis (n = 19, 17.9%), abscess (n = 14 13.2%), pulmonary embolus/deep vein thrombosis (n = 3, 2.8%), small bowel obstruction (n = 2, 1.9%), and fistula (n = 8, 7.5%). Factors that significantly contributed to postoperative complications (P < 0.05) included obesity, diabetes, hypertension, fistula at the time of the operation, a history of >2 prior hernia repairs, a history of >3 prior abdominal operations, hospital stay for >14 days, defect size > 300 square cm, and the use of human-derived mesh allograft. Factors that significantly increased the likelihood of a hernia recurrence (P < 0.05) included a history of >2 prior hernia repairs, the use of human-derived allograft, using an overlay-only mesh placement, and the presence of a postoperative complication, particularly infection. Hernia recurrences were significantly reduced (P < 0.05) by using a "sandwich" repair with both a mesh overlay and underlay and by using component separation.A history of multiple abdominal operations is a major predictor of complications and recurrences. If needed, component separation should be used to achieve primary tension-free closure, which helps to reduce the likelihood of hernia recurrences. Our data suggest that mesh reinforcement used concomitantly in a "sandwich" repair with component separation release may lead to reduced recurrence rates and may provide the optimal repair in complex hernia defects.

Abstract

Injured patients who are not transported by an ambulance to the hospital are often not included in trauma registries. The outcomes of these patients have until now been unknown. Understanding what happens to nontransports is necessary to better understand triage validity, patient outcomes, and costs associated with injury. We hypothesized that a subset of patients who were not transported from the scene would later present for evaluation and that these patients would have a nonzero mortality rate.This is a population-based, retrospective cohort study of injured adults and children for three counties in California from 2006 to 2008. Prehospital data for injured patients for whom an ambulance was dispatched were probabilistically linked to trauma registry data from four trauma centers, state-level discharge data, emergency department records, and death files (1-year mortality).A total of 69,413 injured persons who were evaluated at the scene by emergency medical services were included in the analysis. Of them, 5,865 (8.5%) were not transported. Of those not transported, 1,616 (28%) were later seen in an emergency department and discharged and 92 (2%) were admitted. Seven (0.2%) patients later died.Patients evaluated by emergency medical services, but not initially transported from the field after injury, often present later to the hospital. The mortality rate in this population was not zero, and these patients may represent preventable deaths.III, therapeutic study.

Abstract

since California lacks a statewide trauma system, there are no uniform interfacility pediatric trauma transfer guidelines across local emergency medical services (EMS) agencies in California. This may result in delays in obtaining optimal care for injured children.this study sought to understand patterns of pediatric trauma patient transfers to the study trauma center as a first step in assessing the quality and efficiency of pediatric transfer within the current trauma system model. Outcome measures included clinical and demographic characteristics, distances traveled, and centers bypassed. The hypothesis was that transferred patients would be more severely injured than directly admitted patients, primary catchment transfers would be few, and out-of-catchment transfers would come from hospitals in close geographic proximity to the study center.this was a retrospective observational analysis of trauma patients ≤ 18 years of age in the institutional trauma database (2000-2007). All patients with a trauma International Classification of Diseases, 9th revision (ICD-9) code and trauma mechanism who were identified as a trauma patient by EMS or emergency physicians were recorded in the trauma database, including those patients who were discharged home. Trauma patients brought directly to the emergency department (ED) and patients transferred from other facilities to the center were compared. A geographic information system (GIS) was used to calculate the straight-line distances from the referring hospitals to the study center and to all closer centers potentially capable of accepting interfacility pediatric trauma transfers.of 2,798 total subjects, 16.2% were transferred from other facilities within California; 69.8% of transfers were from the catchment area, with 23.0% transferred from facilities ≤ 10 miles from the center. This transfer pattern was positively associated with private insurance (risk ratio [RR] = 2.05; p < 0.001) and negatively associated with age 15-18 years (RR = 0.23; p = 0.01) and Injury Severity Score (ISS) > 18 (RR = 0.26; p < 0.01). The out-of-catchment transfers accounted for 30.2% of the patients, and 75.9% of these noncatchment transfers were in closer proximity to another facility potentially capable of accepting pediatric interfacility transfers. The overall median straight-line distance from noncatchment referring hospitals to the study center was 61.2 miles (IQR = 19.0-136.4), compared to 33.6 miles (IQR = 13.9-61.5) to the closest center. Transfer patients were more severely injured than directly admitted patients (p < 0.001). Out-of-catchment transfers were older than catchment patients (p < 0.001); ISS > 18 (RR = 2.06; p < 0.001) and age 15-18 (RR = 1.28; p < 0.001) were predictive of out-of-catchment patients bypassing other pediatric-capable centers. Finally, 23.7% of pediatric trauma transfer requests to the study institution were denied due to lack of bed capacity.from the perspective an adult Level I trauma center with a certified pediatric intensive care unit (PICU), delays in definitive pediatric trauma care appear to be present secondary to initial transport to nontrauma community hospitals within close proximity of a trauma hospital, long transfer distances to accepting facilities, and lack of capacity at the study center. Given the absence of uniform trauma triage and transfer guidelines across state EMS systems, there appears to be a role for quality monitoring and improvement of the current interfacility pediatric trauma transfer system, including defined triage, transfer, and data collection protocols.

Abstract

Traumatic blunt aortic injury has traditionally been viewed as a surgical emergency, whereas nonoperative therapy has been reserved for nonsurgical candidates. This study reviews our experience with deliberate, nonoperative management for blunt thoracic aortic injury.A retrospective chart review with selective longitudinal follow-up was conducted for patients with blunt aortic injury. Surveillance imaging with computed tomography angiography was performed. Nonoperative patients were then reviewed and analyzed for survival, evolution of aortic injury, and treatment failures.During the study period, 53 patients with an average age of 45 years (range, 18-80 years) were identified, with 28% presenting to the Stanford University School of Medicine emergency department and 72% transferred from outside hospitals. Of the 53 patients, 29 underwent planned, nonoperative management. Of the 29 nonoperative patients, in-hospital survival was 93% with no aortic deaths in the remaining patients. Survival was 97% at a median of 1.8 years (range, 0.9-7.2 years). One patient failed nonoperative management and underwent open repair. Serial imaging was performed in all patients (average = 107 days; median, 31 days), with 21 patients having stable aortic injuries without progression and 5 patients having resolved aortic injuries.This experience suggests that deliberate, nonoperative management of carefully selected patients with traumatic blunt aortic injury may be a reasonable alternative in the polytrauma patient; however, serial imaging and long-term follow-up are necessary.

Abstract

Delivery of Surgical Critical Care in the United States is facing multiple challenges including increasing complexity of care, escalating costs, shortage of well-trained physicians, and controversies about appropriate training and credentialing methods. In this position paper, the Surgical Critical Care Program Directors Society discusses some of these important issues and suggests a number of possible solutions.

Abstract

In the United States, the Emergency Medical Treatment and Active Labor Act (EMTALA) effectively requires Level I trauma centers to accept hand trauma transfers for higher level of care if capacity exists. However, patient transfer for non-medical reasons, such as ability to pay, is still perceived as a common practice. We hypothesized that EMTALA would cause selective transfer of hand patients who were underinsured or uninsured, thus, effectively burdening a Level I trauma center. A dedicated transfer center documented the demographics and outcomes of all calls for hand trauma transfers from December 2003 to September 2005. This data registry was reviewed for age, gender, race, insurance status, and length of hospital stay. This data was compared with direct admissions to the emergency room for hand emergencies during that same time period. During the 2-year time period, a total of 151 calls for EMTALA transfer were received for hand emergencies. Our institution accepted 92 of these patients for transfer. Reasons for not accepting transfer included lack of bed availability and unavailability of the on-call surgeon due to other emergency operative cases. Compared with hand emergency patients brought directly to our emergency department during the same time period, transferred patients were younger and had a shorter length of stay. Interestingly, they were very similar in terms of sex, race, and insurance status. These data suggest that the primary motivations for EMTALA hand trauma transfers are truly complexity of patient care and specialist availability. Given the often urgent nature of hand trauma surgery and the limited resources available, expansion and development of hand and microsurgery regional centers will be vital to adequately meet demand without overburdening existing centers.

Abstract

Experimentation involving human subjects requires careful attention to the protection of their rights. Beginning with the Belmont Report in 1979, the United States has developed various sets of rules and regulations that identify the requirements for performing human subject research. In addition, these standards attempt to define the fundamental difference between what constitutes research versus clinical treatment versus innovation. We explore the intersection between two areas of independent bioethics, surgical innovation and emergency research; the point we refer to as emergency innovation.A systematic literature review in each of the fields of emergency research and surgical innovation was completed. The ethical principles involved in each field were identified. In addition, a recent case of surgical innovation within the context of emergency treatment is evaluated for the ethics invoked.One of the great challenges in emergency innovation is that the main protection offered in innovation (heightened informed consent) is not possible in the emergency context where in fact informed consent is waived. Interestingly, the rest of the protections outlined for each field are not mutually exclusive. They can and should be utilized in any project that takes place at this intersection. However, as there are no strict regulations in place for the collision of these two fields, the possibility of having the majority of the involved ethical principles misinterpreted or ignored is very real.For emergency innovation, where it is unclear what ethical principles and regulatory powers apply, it is imperative to be unambiguous about the purpose of the investigation, to adhere to all applicable ethical principles, and to have utmost consideration for protection of the research subject. To determine intent, the goals of the study must be outlined precisely - and if those include the prospect of publication, institutional review board (IRB) approval should be involved early. If, however, the innovation is subtle and the goal geared toward improved patient care, a small feasibility trial would be an appropriate first step before transitioning to a formal larger study approved by an IRB. In either case, the degree of the change in practice must be carefully evaluated and the vulnerability of the research subjects respected. With careful attention paid to all applicable ethical principles at the emergency innovation intersection, medical progress can continue at minimized risk to the human subject participants.

Abstract

Exsanguinating hemorrhage necessitating massive blood product transfusion is associated with high mortality rates. Recent data suggest that altering the fresh frozen plasma to packed red blood cell ratio (FFP:PRBC) results in significant mortality reductions. Our purpose was to evaluate mortality and blood product use in the context of a newly initiated massive transfusion protocol (MTP).In July 2005, our American College of Surgeons-verified Level I trauma center implemented an MTP supporting a 1:1.5 FFP:PRBC ratio, improved communications, and enhanced systems flow to optimize rapid blood product availability. During the 4 years surrounding protocol implementation, we reviewed data on trauma patients directly admitted through the emergency department and requiring 10 or more units PRBCs during the first 24 hours.For the 2 years before and subsequent to MTP initiation, there were 4,223 and 4,414 trauma activations, of which 40 and 37 patients, respectively, met study criteria. The FFP:PRBC ratios were identical, at 1:1.8 and 1:1.8 (p = 0.97). Despite no change in FFP:PRBC ratio, mortality decreased from 45% to 19% (p = 0.02). Other significant findings included decreased mean time to first product: cross-matched RBCs (115 to 71 minutes; p = 0.02), FFP (254 to 169 minutes; p = 0.04), and platelets (418 to 241 minutes; p = 0.01).MTP implementation is associated with mortality reductions that have been ascribed principally to increased plasma use and decreased FFP:PRBC ratios. Our study found a significant reduction in mortality despite unchanged FFP:PRBC ratios and equivalent overall mean numbers of transfusions. Our data underscore the importance of expeditious product availability and emphasize that massive transfusion is a complex process in which product ratio and time to transfusion represent only the beginning of understanding.

Abstract

To correlate deficient pituitary function with life satisfaction and functional performance in subjects with a recent history of traumatic brain injury (TBI) and subarachnoid haemorrhage (SAH).Cross-sectional study.Eighteen subjects with TBI and 16 subjects with SAH underwent pituitary hormonal and functional assessments 5-12 months following the event. Adrenal reserve was assessed with a 1 mcg cosyntropin stimulation test and growth hormone deficiency (GHD) was diagnosed by insufficient GH response to GHRH-Arginine stimulation. Assessments of life satisfaction and performance-function included the Satisfaction with Life Scale (SWLS), Craig Handicap Assessment and Reporting Technique (CHART) and the Mayo Portland Adaptability Inventory-4 (MPAI-4).Hypopituitarism was present in 20 (58.8%) subjects, including 50% with adrenal insufficiency. Hypothyroidism correlated with worse performance on SWLS and CHART measures. GHD was associated with poorer performance on CHART and MPAI-4 scale.In this series of subjects with history of TBI and SAH, hypothyroidism and GHD were associated with diminished life satisfaction and performance-function on multiple assessments. Further studies are necessary to determine the appropriate testing of adrenal reserve in this population and to determine the benefit of pituitary hormone replacement therapy on function following brain injury.

Abstract

After an unsuccessful American College of Surgery Committee on Trauma visit, our level I trauma center initiated an improvement program that included (1) hiring new personnel (trauma director and surgeons, nurse coordinator, orthopedic trauma surgeon, and registry staff), (2) correcting deficiencies in trauma quality assurance and process improvement programs, and (3) development of an outreach program. Subsequently, our trauma center had two successful verifications. We examined the longitudinal effects of these efforts on volume, patient outcomes and finances.The Trauma Registry was used to derive data for all trauma patients evaluated in the emergency department from 2001 to 2007. Clinical data analyzed included number of admissions, interfacility transfers, injury severity scores (ISS), length of stay, and mortality for 2001 to 2007. Financial performance was assessed for fiscal years 2001 to 2007. Data were divided into patients discharged from the emergency department and those admitted to the hospital.Admissions increased 30%, representing a 7.6% annual increase (p = 0.004), mostly due to a nearly fivefold increase in interfacility transfers. Severe trauma patients (ISS >24) increased 106% and mortality rate for ISS >24 decreased by 47% to almost half the average of the National Trauma Database. There was a 78% increase in revenue and a sustained increase in hospital profitability.A major hospital commitment to Committee on Trauma verification had several salient outcomes; increased admissions, interfacility transfers, and acuity. Despite more seriously injured patients, there has been a major, sustained reduction in mortality and a trend toward decreased intensive care unit length of stay. This resulted in a substantial increase in contribution to margin (CTM), net profit, and revenues. With a high level of commitment and favorable payer mix, trauma center verification improves outcomes for both patients and the hospital.

Abstract

Efforts to determine the suitability of low-grade pancreatic injuries for nonoperative management have been hindered by the inaccuracy of older computed tomography (CT) technology for detecting pancreatic injury (PI). This retrospective, multicenter American Association for the Surgery of Trauma-sponsored trial examined the sensitivity of newer 16- and 64-multidetector CT (MDCT) for detecting PI, and sensitivity/specificity for the identification of pancreatic ductal injury (PDI).Patients who received a preoperative 16- or 64-MDCT followed by laparotomy with a documented PI were enrolled. Preoperative MDCT scans were classified as indicating the presence (+) or absence (-) of PI and PDI. Operative notes were reviewed and all patients were confirmed as PI (+), and then classified as PDI (+) or (-). As all patients had PI, an analysis of PI specificity was not possible. PI patients formed the pool for further PDI analysis. As sensitivity and specificity data were available for PDI, multivariate logistic regression was performed for PDI patients using the presence or absence of agreement between CT and operative note findings as an independent variable. Covariates were age, gender, Injury Severity Score, mechanism of injury, presence of oral contrast, presence of other abdominal injuries, performance of the scan as part of a dedicated pancreas protocol, and image thickness < or =3 mm or > or =5 mm.Twenty centers enrolled 206 PI patients, including 71 PDI (+) patients. Intravenous contrast was used in 203 studies; 69 studies used presence of oral contrast. Eight-nine percent were blunt mechanisms, and 96% were able to have their duct status operatively classified as PDI (+) or (-). The sensitivity of 16-MDCT for all PI was 60.1%, whereas 64-MDCT was 47.2%. For PDI, the sensitivities of 16- and 64-MDCT were 54.0% and 52.4%, respectively, with specificities of 94.8% for 16-MDCT scanners and 90.3% for 64-MDCT scanners. Logistic regression showed that no covariates were associated with an increased likelihood of detecting PDI for either 16- or 64-MDCT scanners. The area under the curve was 0.66 for the 16-MDCT PDI analysis and 0.77 for the 64-MDCT PDI analysis.Sixteen and 64-MDCT have low sensitivity for detecting PI and PDI, while exhibiting a high specificity for PDI. Their use as decision-making tools for the nonoperative management of PI are, therefore, limited.

Abstract

Triage of the trauma patient in the field is a complex and challenging issue, especially deciding when to use aeromedical transport. The American College of Surgeons Committee on Trauma recently defined an acceptable under-triage rate [seriously injured patient not taken to a trauma center (TC)] as 5%, whereas over-triage rates may be as high as 25% to 50%. Effective utilization of prehospital helicopter transport requires both accurate assessment of patients and effective communication. The rural county adjacent to our developed trauma system uses standardized triage criteria to identify patients for direct transport to our TCs. We hypothesized these criteria accurately identify major trauma victims (MTV) and further that communication could be simplified to expedite transport.Prehospital personnel use a MAP (mechanism, anatomy, and physiology) scoring system to triage trauma patients. Patients with > or = 2 "hits" are defined as MTV. In 2004, the triage policy was changed so that MTV would be transported directly to a TC without base hospital consultation (previously required). The Emergency Medical Services (EMS) Medical Director reviewed cases transported to the TC to determine the appropriateness of triage decisions (over- and under-triage using the American College of Surgeons Committee on Trauma definitions). Data were compared before and after this policy change.For 2004 to 2006, we evaluated 676 air transports to TC and compared them to 468 in the prior 56 months. The overall transport rate increased slightly 7% to 10%. During the study period the over-triage rate was 31% compared with 21%, before the policy change. The MAP triage tool yielded a 93.8% sensitivity and a 99.5% specificity. Therefore, it determined the need for air-medical transport out of a rural environment into an established trauma system with > 90% accuracy.Prehospital personnel can accurately use a trauma triage tool to identify MTV. Eliminating base station contact, a potential for introducing communication error, did increase over-triage but still well within accepted limits. The system change also resulted in the transport of a greater proportion of minor trauma patients who later proved to have major injuries.

Abstract

Strict glucose control with insulin is associated with decreased mortality in a mixed patient population in the intensive care unit. Controversy exists regarding the relative benefits of glucose control versus a direct advantageous effect of exogenous insulin. As a combined medical/surgical population differs significantly from the critically injured patient primed for secondary insult, our purpose was to determine the influence of insulin on activated macrophages. Our hypothesis was that insulin would directly abrogate the inflammatory cascade.Differentiated human monocytic THP-1 cells were stimulated with endotoxin (lipopolysaccharide [LPS], 100 ng/mL) for 6 hours. Cells were treated +/-10(-7) M insulin for 1 hour and 24 hours. Total RNA was isolated and gene expression for TNF-alpha and IL-6 performed using Q-RT-PCR. Supernatants were assayed for TNF-alpha and IL-6 protein by ELISA.At 1 hour, compared with macrophages treated with LPS alone, macrophages treated with insulin produced significantly more TNF-alpha protein (11.4 +/- 5.9 pg/mL vs. 32.5 +/- 3.1 pg/mL; p < 0.03). At 24 hours compared with macrophages treated with LPS alone, macrophages treated with insulin produced significantly more TNF-alpha protein (83 +/- 2.02 pg/mL vs. 114 +/- 6.54 pg/mL; p < 0.01). However, gene expression of TNF-alpha and IL-6 was not different in LPS stimulated macrophages with and without insulin treatment at both 1 hour and 24 hours.Contrary to our hypothesis, insulin does not have direct anti-inflammatory properties in this experimental model. In fact, insulin increases proinflammatory cytokine protein levels from activated macrophages.

Abstract

Trauma surgery has changed significantly over the past decade. Nonoperative evidence-based algorithms have become common and surgical trauma volume has become increasingly difficult to maintain. The acute care surgery (ACS) model, which integrates trauma, critical care, and emergency surgery, has been proposed as a future model of trauma practice.Database information from an academic, county-based, trauma center was reviewed. A performance improvement surgical procedure database and level I trauma registry from 2005 were used to evaluate one center's ACS practice.There were 2,276 cases performed by 7 full-time and 5 part-time surgeons. Elective cases accounted for 64% (1,480) of caseload, emergency/urgent general surgery accounted for 32% (719) of cases, and emergency trauma surgeries accounted for 4% (96 procedures in 77 patients). In all, 23% were performed after hours. The ACS model supported controllable hours, adequate surgical volume, excellent patient care, and an appealing clinical practice.Surgical practice in a county-run trauma hospital can be similar to the ACS model, with positive results in terms of clinical volume and physician satisfaction. As clinical practices shift to the ACS model, there are lessons to be learned from currently existing, thriving, long-standing similar prototypes.

Abstract

During the past 40 years, management of solid organ injury in pediatric trauma patients has shifted to highly successful nonoperative management. Our purpose was to characterize children requiring operative intervention. We hypothesized that older children would be more likely to require operative intervention. In particular, we wanted to examine potential outcome disparities between children who were operated upon immediately and those in whom attempted nonoperative management failed. Additionally, we asked whether attempted nonoperative management, when failed, put children at higher risk for mortality or morbidities such as increased blood product transfusions or lengths of stays.Retrospective cohorts from seven Level I pediatric trauma centers were identified. Blunt splenic, hepatic, renal, or pancreatic injuries were documented in 2,944 children <1 to 19 years of age from January 1993 to December 2002. Data collected included demographics, hemodynamics, blood transfusions, Glasgow Coma Scale score, Injury Severity Score, hospital length of stay (LOS), intensive care unit (ICU) LOS, and mortality. Analysis involved 140 (4.8%) of 2,944 patients requiring operation. Two cohorts were characterized: (1) immediate operation (IO), defined as laparotomy =3 hours after arrival (n = 81; 58%) and (2) failed nonoperative management (F-NOM), defined as laparotomy >3 hours after arrival (n = 59; 42%).Comparing the two cohorts, no age differences were found. Compared with F-NOM, IO had significantly worse hemodynamics, Injury Severity Score, and Glasgow Coma Scale score and was associated with liver injuries. Pancreatic injuries were significantly associated with F-NOM. While controlling for injury severity to compare IO versus F-NOM, linear regression revealed equivalent blood transfusions, ICU LOS, hospital LOS, and mortality rates.IO and F-NOM are rare events and independent of age. When operated upon for appropriate physiology, the timing of operation in pediatric solid organ injury is irrelevant and not detrimental with respect to blood transfusion, mortality, ICU and hospital LOS, and resource utilization.

Abstract

More than one third of adults over the age of 65 suffer a fall each year, facing morbidity and mortality. Modifiable risk factors for falls have been identified, but specific recruitment strategies for prevention programs have not been evaluated. The purpose of this observational study was to evaluate recruitment strategies for a fall prevention program.Participants were recruited during an 11-month period at a Level I trauma center. Participants were eligible if >65 years old, living independently, and had a fall. Recruitment modalities included (1) emergency medical services, (2) emergency department (ED), (3) primary care providers, and (4) media exposure leading to self-referral. Data were collected on baseline rate of fall victims seen in the ED, demographics, medical history, and source of referral.There were 91 individuals referred, with 61 (67%) enrolled. Enrollment rates were higher among patients referred by self or primary care providers than among those referred by emergency medical services or the ED. There were no significant differences in demographics or medical history among the eligible but not referred ED population, the referred population, and the enrolled population. Reasons for not enrolling included inappropriate referral (33%), no response (17%), other illness (13%), and patients thinking that they do not need the services (37%).These recruitment strategies were successful in enrolling a representative population of patients at risk for recurrent falls, but could be improved to capture more potential participants. Source of referral has a significant effect on rate of enrollment. We outline challenges and solutions to recruitment.

Abstract

The Emergency Medical Treatment and Active Labor Act (EMTALA) effectively requires Level I trauma centers (TC) to accept all transfers for a higher level of care if capacity exists. We hypothesized that EMTALA would burden a Level I TC by a selective referral of a poor payer mix of primarily nonoperative patients.All transfer calls (December 2003 and September 2005) to our Level I TC are handled by a dedicated transfer center. Calls were reviewed for age, surgical service requested, and outcome of request. The trauma registry was queried to compare Injury Severity Scale (ISS) score, hospital stay (LOS), operations, mortality, and payer status for transfer and primary catchment patients.In all, 821 calls were received; 77 calls were cancelled by the referring hospital and 52 were for consultation only. Of the 692 transfer requests, 534 (77%) were accepted, 134 (19%) were denied for no capacity, and only 24 (4%) were declined by TC as not clinically indicated. Transferred patients were younger (32.0 +/- 1.49 versus 38.9 +/- 0.51, p < 0.05), had similar ISS scores (13.6 +/- 0.62 versus 13.7 +/- 0.26) and LOS (7.0 +/- 0.70 versus 7.4 +/- 0.25), but were somewhat more likely to require an operation than direct admissions (58% versus 51%, p < 0.05). Although trauma (24%) and neurosurgery (24%) were the most commonly requested services, followed by orthopedics (20%), orthopedics accounted for 60% of operations on transferred patients compared with 10% to 13% for trauma and neurosurgery (mostly spine). There was no difference in the payer status of transfer and direct admit patients.Contrary to our assumptions, EMTALA patients had an identical payer mix and similar operative need compared with our primary catchment patients. They do represent a large additional patient load (20% of admissions) and differentially impact specialists, mostly operative for orthopedics and complex nonoperative care for trauma and neurosurgery. These data suggest that the primary motivations for transfer are specialist availability and complexity of care rather than financial concerns. As TCs provide backup specialty call coverage for a wide geographic area, this further supports the need for trauma systems development.

Abstract

Despite significant risk for venous thromboembolism, severely injured trauma patients often are not candidates for prophylaxis or treatment with anticoagulation. Long-term inferior vena cava (IVC) filters are associated with increased risk of postphlebitic syndrome. Retrievable IVC filters potentially offer a better solution, but only if the filter is removed; our hypothesis is that the most of them are not.This retrospective study queried a level I trauma registry for IVC filter insertion from September 1997 through June 2004.One IVC filter was placed before the availability of retrievable filters in 2001. Since 2001, 27 filters have been placed, indicating a change in practice patterns. Filters were placed for prophylaxis (n = 11) or for therapy in patients with pulmonary embolism or deep vein thrombosis (n = 17). Of 23 temporary filters, only 8 (35%) were removed.Surgeons must critically evaluate indications for IVC filter insertion, develop standard criteria for placement, and implement protocols to ensure timely removal of temporary IVC filters.

Abstract

Trauma surgery as a specialty in the United States is at a crossroads. Currently, less than 100 residents per year pursue additional specialty training in trauma and surgical critical care. Many forces have converged to place serious challenges and obstacles to the training of future trauma surgeons. In order for the field to flourish, the training of future trauma surgeons must be modified to compensate for these changes.Recent medical literature regarding the training of trauma surgeons and report of the Future of Trauma Surgery/Trauma Specialization Committee of the American Association for the Surgery of Trauma.The new post-graduate trauma training fellowship of the future should be built on a foundation of general surgery. The goal of this program will be to train a surgeon with broad expertise in trauma, critical care, and emergency general surgery. This new emphasis on non-trauma emergency surgery required an image change and thus a new name; Acute Care Surgery: Trauma, Critical Care, and Emergency Surgery.

Abstract

Our goal was to identify factors that can be targeted during medical education to encourage a career in surgery.We conducted a cross-sectional survey of first and fourth year classes in a Liaison Committee on Medical Education-accredited medical school. Students scored 19 items about perceptions of surgery using a Likert-type scale. Students also indicated their gender and ranked their top three career choices.There were 121 of 210 (58%) first year and 110 of 212 (52%) fourth year students who completed the survey. First year students expressed a positive correlation between surgery and career opportunities, intellectual challenge, performing technical procedures, and obtaining a residency position, although length of training, work hours, and lifestyle during and after training were negatively correlated with choosing surgery. Fourth year student responses correlated positively with career and academic opportunities, intellectual challenge, technical skills, role models, prestige, and financial rewards. Factors that correlated negatively were length of training, residency lifestyle, hours, call schedule, and female gender of the student respondent. Forty-four percent of first year male students expressed an interest in surgery versus 27% of fourth year male students (p < 0.04). Eighteen percent of first year female students expressed an interest in surgery versus 5% of fourth year female students (p < 0.006).Lifestyle issues remain at the forefront of student concerns. Intellectual challenge, career opportunities, and technical skills are consistently recognized as strengths of surgery. Additionally, fourth year students identify role models, prestige, and financial rewards as positive attributes. Emphasizing positive aspects may facilitate attracting quality students to future careers in surgery.

Abstract

Elevated residual volumes (RV), considered a marker for the risk of aspiration, are used to regulate the delivery of enteral tube feeding. We designed this prospective study to validate such use.Critically ill patients undergoing mechanical ventilation in the medical, coronary, or surgical intensive care units in a university-based tertiary care hospital, placed on intragastric enteral tube feeding through nasogastric or percutaneous endoscopic gastrostomy tubes, were included in this study. Patients were fed Probalance (Nestle USA) to provide 25 kcal/kg per day (to which 10 yellow microscopic beads and 4.5 mL of blue food coloring per 1,500 mL was added). Patients were randomized to one of two groups based on management of RV: cessation of enteral tube feeding for RV >400 mL in study patients or for RV >200 mL in controls. Acute Physiology and Chronic Health Evaluation (APACHE) III, bowel function score, and aspiration risk score were determined. Bedside evaluations were done every 4 hrs for 3 days to measure RV, to detect blue food coloring, to check patient position, and to collect secretions from the trachea and oropharynx. Aspiration/regurgitation events were defined by the detection of yellow color in tracheal/oropharyngeal samples by fluorometry. Analysis was done by analysis of variance, Spearman's correlation, Student's t-test, Tukey's method, and Cochran-Armitage test.Forty patients (mean age, 44.6 yrs; range, 18-88 yrs; 70% male; mean APACHE III score, 40.9 [range, 12-85]) were evaluated (21 on nasogastric, 19 on percutaneous endoscopic gastrostomy feeds) and entered into the study. Based on 1,118 samples (531 oral, 587 tracheal), the mean frequency of regurgitation per patient was 31.3% (range, 0% to 94%), with a mean RV for all regurgitation events of 35.1 mL (range, 0-700 mL). The mean frequency of aspiration per patient was 22.1% (range, 0% to 94%), with a mean RV for all aspiration events of 30.6 mL (range, 0-700 mL). The median RV for both regurgitation and aspiration events was 5 mL. Over a wide range of RV, increasing from 0 mL to >400 mL, the frequency of regurgitation and aspiration did not change appreciably. Aspiration risk and bowel function scores did not correlate with the incidence of aspiration or regurgitation. Blue food coloring was detected on only three of the 1,118 (0.27%) samples. RV was < or =50 mL on 84.1% and >400 mL on 1.4% of bedside evaluations. Sensitivities for detecting aspiration per designated RV were as follows: 400 mL = 1.5%; 300 mL = 2.3%; 200 mL = 3.0%; and 150 mL = 4.5%. Low RV did not assure the absence of events, because the frequency of aspiration was 23.0% when RV was <150 mL. Raising the designated RV for cessation of enteral tube feeding from 200 mL to 400 mL did not increase the risk, because the frequency of aspiration was no different between controls (21.6%) and study patients (22.6%). The frequency of regurgitation was significantly less for patients with percutaneous endoscopic gastrostomy tubes compared with those with nasogastric tubes (20.3% vs. 40.7%, respectively; p = .046). There was no correlation between the incidence of pneumonia and the frequency of regurgitation or aspiration.Blue food coloring should not be used as a clinical monitor. Converting nasogastric tubes to percutaneous endoscopic gastrostomy tubes may be a successful strategy to reduce the risk of aspiration. No appropriate designated RV level to identify aspiration could be derived as a result of poor sensitivity over a wide range of RV. Study results do not support the conventional use of RV as a marker for the risk of aspiration.

Abstract

Resuscitation from hemorrhagic shock is associated with impairment of the endothelium-dependent dilation response, whereas the dilation response induced by the endothelium-independent pathway, which is mediated by nitroprusside, a nitric oxide (NO) donor and a direct activator of guanylate cyclase, remains unaltered. Whether the impairment of the endothelium-dependent dilation response is caused by a specific receptor alteration or generally a defect in signal transduction pathway remains undetermined. Anesthetized rats were monitored for hemodynamics, and the terminal ileum was prepared for intravital videomicroscopy. Hemorrhage was 50% of mean arterial pressure for 60 min followed by resuscitation with the shed blood returned plus 2 volumes of normal saline. Intestinal microvascular reactivity to the endothelium-dependent receptor-dependent agonists acetylcholine or substance P (10(-8) or 10(-6) M), as well as the endothelium-dependent receptor-independent calcium ionophore, was determined at baseline and at 2 h postresuscitation from hemorrhagic shock. Measured vascular diameters for premucosal A3 arterioles (pA3 and dA3) were normalized and expressed as percentage of the maximal dilation capacity, as obtained from the response to the endothelium-independent NO donor sodium nitroprusside (10(-4) M). At 2 h postresuscitation, there was a marked constriction of pA3 (-70.1 +/- 20) and dA3 (-61.5 +/- 11.6) from maximal dilation capacity. Baseline premucosal arteriolar response to substance P (10(-8) M) was 30.68 +/- 4.19% and 34.66 +/- 5.82% for pA3 and dA3 arterioles, respectively. This was significantly reduced to 20.97 +/- 2.41% and 17.94 +/- 3.60% at 2 h postresuscitation. However, no significant difference between baseline and postresuscitation arteriolar responses was observed at the higher dose of substance P (10(-6) M). Postresuscitation premucosal arteriolar response to the endothelium-dependent receptor-independent calcium ionophore (10(-9) to 10(-5) M) is characterized by a marked decrease in sensitivity and an enhanced threshold for calcium ionophore-mediated dilation. The logEC50 was -7.62 +/- 0.39 and -7.75 +/- 0.32 for the pA3 and dA3 at baseline, respectively. This was significantly (P < 0.01) reduced to -5.15 +/- 0.14 and -4.39 +/- 0.71 at 2 h postresuscitation. These data suggest that impairment of the endothelium-dependent dilation response after resuscitation from hemorrhagic shock is not mediated by specific receptor alteration. Cellular mechanisms that participate in or are part of oxygen free radical formation after resuscitation from hemorrhagic shock such as Ca2+ and leukocytes, appear to have a pivotal role in the mechanism of cellular dysfunction.

Abstract

Intra-abdominal infection is common and frequently seen by the surgeon. Mortality is related to disease acuity and organ failure. This report, based on medical literature and personal experience, is a brief review of this subject, highlighting important historical milestones and recent advances in surgical and antibiotic therapy. Peritonitis remains a clinical challenge. Aggressive resuscitation, diagnostic imaging, and surgical treatment are the mainstays of appropriate therapy. Percutaneous drainage of intra-abdominal collections has increased over time and is particularly helpful in certain postoperative patients. Adjunctive antibiotic therapy against gram-negative aerobes and anaerobes should be limited to a 7- to 10-day course, except in selected patients, such as those with inadequate source controls.

Abstract

To study the effects of peritoneal resuscitation from hemorrhagic shock.Methods for conventional resuscitation (CR) from hemorrhagic shock (HS) often fail to restore adequate intestinal blood flow, and intestinal ischemia has been implicated in the activation of the inflammatory response. There is clinical evidence that intestinal hypoperfusion is a major factor in progressive organ failure following HS. This study presents a novel technique of peritoneal resuscitation (PR) that improves visceral perfusion.Male Sprague-Dawley rats were bled to 50% of baseline mean arterial pressure (MAP) and resuscitated with shed blood plus 2 equal volumes of saline (CR). Groups were 1) sham, 2) HS + CR, and 3) HS + CR + PR with a hyperosmolar dextrose-based solution (Delflex 2.5%). Groups 1 and 2 had normal saline PR. In vivo videomicroscopy and Doppler velocimetry were used to assess terminal ileal microvascular blood flow. Endothelial cell function was assessed by the endothelium-dependent vasodilator acetylcholine.Despite restored heart rate and MAP to baseline values, CR animals developed a progressive intestinal vasoconstriction and tissue hypoperfusion compared to baseline flow. PR induced an immediate and sustained vasodilation compared to baseline and a marked increase in average intestinal blood flow during the entire 2-hour post-resuscitation period. Endothelial-dependent dilator function was preserved with PR.Despite the restoration of MAP with blood and saline infusions, progressive vasoconstriction and compromised intestinal blood flow occurs following HS/CR. Hyperosmolar PR during CR maintains intestinal blood flow and endothelial function. This is thought to be a direct effect of hyperosmolar solutions on the visceral microvessels. The addition of PR to a CR protocol prevents the splanchnic ischemia that initiates systemic inflammation.

Abstract

The use of steady state as the endpoint for performance of indirect calorimetry (IC) is controversial. We designed this prospective study to evaluate the necessity and significance of achieving steady state.Patients with respiratory failure placed on mechanical ventilation in a short- or long-term acute care unit at any 1 of 3 university-based urban hospitals were eligible for the study. The 24-hour total energy expenditure (TEE) was determined by a Nellcor Puritan Bennett 7250 continuous IC monitor. Measured gas exchange parameters were obtained and averaged every 1 minute for the initial hour and then every 15 minutes for the next 23 hours. Over the initial hour, resting energy expenditure (REE) was averaged for intervals over the first 20, 30, 40, and 60 minutes, and for various definitions of steady state where oxygen consumption (VO2) and carbon dioxide production (VCO2) changed by <10%, 15%, and 20%. Coefficient of variation (CV) was calculated for VO2 over the first 30 minutes of study.Twenty-two patients (mean age, 52.8 years, 59% male, mean Acute Physiology and Chronic Health Evaluation (APACHE III) score 42.0) were entered in the study. The best correlation between short-term "snapshot" REE and the 24-hour TEE was achieved by the steady-state period defined by the most stringent criteria (change in VO2 and VCO2 by <10%). The average REE for all steady-state and interval periods correlated significantly to TEE with no significant difference in the absolute values for REE and TEE. Adding 10% for an activity factor to the average REE for each steady-state and interval period again correlated to TEE in a similar fashion with the same R value, but the absolute values for REE + 10% for all steady-state and interval periods were significantly different than the corresponding TEE. In those patients with less variation (CV for VO2 < or = 9.0), the REE obtained for the steady-state period defined by the most stringent criteria still had the best correlation, but similar correlation could be obtained by interval testing of > or = 30-minute duration. In those patients with greater variation (CV for VO2 >9.0), interval testing of at least 60 minutes or more was required to attain levels of correlation similar to that achieved by the steady-state period defined by the most stringent criteria.These data support the use of steady state, best defined as an interval of 5 consecutive minutes whereby VO2 and VCO2 change by <10%. The mean REE from this period correlates best to the 24-hour TEE regardless of CV. IC testing can be completed after achievement of steady state. Activity factors of 10% to 15% should not be added to the steady-state REE, because this practice significantly decreases the accuracy. In patients who fail to achieve steady state, the CV helps to determine the appropriate duration of IC testing. In those patients with a low CV (< or = 9.0), 30-minute test duration is adequate. In patients with CV >9.0, test duration of at least 60 minutes may be required. These latter patients should be considered for 24-hour IC testing.

Abstract

Endothelial cell dysfunction occurs during hemorrhagic shock (HS) and persists despite adequate resuscitation (RES) that restores and maintains hemodynamics. We hypothesize that RES from HS with crystalloid solutions alone aggravate the endothelial cell dysfunction. To test this hypothesis, anesthetized nonheparinized rats were monitored for hemodynamics, and the terminal ileum was studied with intravital video microscopy. HS was 50% of mean arterial pressure (MAP) for 60 min. Four hemorrhaged groups (10 animals in each group) were randomized for RES: group I with shed blood returned + equal volume of normal saline (NS); group II with shed blood returned + 2x NS; group III with 2x NS only; and group IV with 4x NS only. Two hours post-RES, endothelial cell function was assessed with the endothelial-dependent agonist acetylcholine (ACh, 10(-9)-10(-4) M). Maximum arteriolar diameter was elicited by the endothelial-independent agonist sodium nitroprusside (NTP, 10(-4) M). HS caused a selective vasoconstriction associated with low blood flow in inflow A1 arterioles in all hemorrhaged groups. Post-RES vasoconstriction developed in A1 and premucosal arterioles (pA3 and dA3) In all hemorrhaged groups regardless of the RES regimen. However, A1 vasoconstriction and flow were significantly worst in the animals RES with NS alone (-43% and -75%, respectively) compared with those resuscitated with blood and NS (-27% and -57%). Impaired dilation response to ACh was noted in all hemorrhaged animals. However, a significant shift to the right of the dose-response curve (decreased sensitivity) was observed in the animals resuscitated with NS alone irrespective of the RES volume. These animals required at least two orders of magnitude greater ACh concentration to produce a 20% dilation response. For all vessel types, Group II had the best preservation of endothelial cell function. In conclusion, HS causes a selective vasoconstriction of A1 arterioles, which was not observed in A3 vessels. RES from HS results in progressive vasoconstriction in all intestinal arterioles irrespective of the RES regimen. Crystalloid RES after HS does not restore hemodynamics to baseline and is associated with a marked endothelial cell dysfunction. Blood-containing RES regimens preserve and maintain hemodynamics and are associated with the least microvascular dysfunction. Therefore, regimens for RES from HS must contain blood. Endothelial cell dysfunction is not the sole etiologic factor of post-RES microvascular impairment.

When is the seriously ill patient ready to be fed?JPEN. Journal of parenteral and enteral nutritionSpain, D. A.2002; 26 (6): S62-5

Abstract

After assessing the critically ill patient for risk of aspiration, the clinician still must decide if the patient is ready to be fed. The goal is to identify critically ill patients who are likely to tolerate enteral nutrition and attempt to minimize complications.A synthesis of the both clinical and animal studies to identify factors related to patient readiness for enteral nutrition.The key issue to be resolved is adequacy of resuscitation and restoration of mesenteric perfusion. Currently, there is no reliable clinical tool to measure gut perfusion. The best indicators currently are stabilization of vital signs, decreasing fluid and blood requirements, normalization of the base deficit, and lactate and removal of inotropic or vasopressor support.Most critically ill patients should be ready for enteral nutrition within 24 to 48 hours of intensive care unit admission. Critically ill patients who need catecholamine support, heavy sedation, or therapeutic neuromuscular blockade should probably not receive enteral nutrition until they have been stabilized.

Abstract

The development of delirium tremens (DT) is associated with significant morbidity and mortality. This study identifies characteristics in trauma patients that are predictive of DT.Data from 1,856 trauma patients who either developed DT (n = 105) or had a positive blood alcohol concentration but did not develop DT (n = 1,751) were collected from the trauma registry of a Level I trauma center. Odds ratios were used to measure the association between predictors and DT as an outcome and between DT and length of stay as an outcome.Of seven significant (p < 0.05) predictors of DT, four were retained after stepwise logistic regression: age >40, white race, burn as a mechanism of injury and, as a negative predictor, motor vehicle collision as a mechanism of injury. The DT group stayed an average of 6.5 and 5.2 days longer in the hospital and the intensive care unit, respectively, than those in the control group.It is possible to determine which intoxicated trauma patients are at increased risk for DT using the above predictors. Patients who develop DT have worse outcomes than those who do not. Whether routine DT prophylaxis would improve outcomes among those at increased risk for DT is unknown, but deserves further study.

Abstract

Current evaluation of patients with negative findings on a focused abdominal sonography for trauma scan and an isolated increase of admission hepatic enzymes includes abdominal computed tomography (CT). Many of these patients do not have clinically important hepatic injuries. The purpose of this study was to establish the admission aspartate aminotransferase (AST) level below which patients do not need an abdominal CT for injury evaluation and treatment.Patients who were hemodynamically stable, had a focused abdominal sonography for trauma scan with negative findings, and an AST level greater than 200 IU/L were identified over a 1-year period. Medical records were reviewed for demographics, injuries sustained, mechanism, evaluation, interventions, and complications.A total of 67 patients, mostly with blunt trauma, were identified; 42 (63%) had an AST level < 360 IU/L, and 25 (37%) had an AST level > 360 IU/L. Patients with an AST level > 360 IU/L had a 88% chance of having any hepatic injury and a 44% chance of having an injury of grade III or greater (P =.0001). Patients with an AST level of < 360 IU/L only had a 14% chance of having a liver injury and no chance of having an injury of grade III or greater (P =.036).Clinically important hepatic injuries are not missed if an abdominal CT is only performed for patients with a focused abdominal sonography for trauma scan with negative findings and an AST level of > 360 IU/L. Eliminating unnecessary CT allows for more cost-effective use of resources.

Abstract

Conventional peritoneal dialysis solutions are vasoactive. This vasoactivity is attributed to hyperosmolality and lactate buffer system. This study was conducted to determine if the vasodilator property of commercial peritoneal dialysis solutions is a global phenomenon across microvascular levels, or if this vasodilation property is localized to certain vessel types in the small intestine.Experimental study in a standard laboratory facility.Hemodynamics of anesthetized rats were monitored while the terminal ileum was prepared for in vivo intravital microscopy. Vascular reactivity of inflow arterioles (A1), branching (A2), and arcade, as well as pre-mucosal (A3) arterioles was assessed after suffusion of the terminal ileum with a non-vasoactive solution or a commercial 4.25% glucose-based solution (Delflex; Fresenius USA, Ogden, Utah, USA). Vascular reactivity of three different level venules was also assessed. Maximum dilation response was obtained from sequential applications of the endothelial-dependent dilator, acetylcholine (10(-5) mol/L), and the endothelial-independent nitric oxide donor, sodium nitroprusside (NTP; 10(-4) mol/L).Delflex induced an instant and sustained vasodilation that averaged 28.2% +/- 2.4% of baseline diameter in five different-level arterioles, ranging in size between 7 mu and 100 mu. No significant vascular reactivity was observed in three different-level venules. Delflex increased intestinal A1 blood flow from baseline 568 +/- 31 nL/ second to 1,049 +/- 46 nL/sec (F= 24.7, p< 0.001). Similarly, intestinal venous outflow increased to 435 +/- 17 nL/sec from a baseline outflow of 253 +/- 59 nL/sec (F= 4.7, p < 0.05). Adjustment of the initial pH of Delflex from 5.5 to 7.4 resulted in similar microvascular responses before pH adjustment.Ex vivo exposure of intestinal arterioles to conventional peritoneal dialysis solutions produces a sustained and generalized vasodilation. This vasoactivity is independent of arteriolar level and the pH of the solution. Dialysis solution-mediated vasodilation is associated with doubling of A1 intestinal arteriolar blood flow. Addition of NTP at an apparent clinical dose does not appear to produce any further significant arteriolar dilation than that induced by dialysis solution alone. Experimental data that estimate the exchange vessel surface area per unit volume of tissue will be required to make a correlation with permeability in order to extrapolate our findings to clinical in vivo conditions.

Abstract

Clinical studies show that immune-enhancing enteral diets (IED; with L-arginine, fish oil, and RNA fragments) decrease the rate of sepsis and shorten the length of hospital stay after the start of enteral feeding. These beneficial effects are dependent on the route of administration (enteral vs parenteral) and on the nutrient composition (IED vs standard diets). Gut exposure to an IED seems to preserve and/or augment intestinal mucosal immunity. However, nutrient absorption stimulates gut blood flow in a nutrient-specific manner (i.e., postprandial hyperemia). We hypothesized that an IED would initiate a different pattern of whole organ blood flow compared to a standard diet. This suggests that a mechanism for the protective effect of IED might be the preferential augmentation of gut blood flow to gut-associated lymphoid tissue (GALT) or mucosa-associated lymphoid tissue (MALT).Male Sprague-Dawley rats (200-225 g) were anesthetized and cannulated for colorimetric microsphere determination of blood flow distribution (with the phantom organ technique). Animals received gastric gavage (2 ml) of an IED (Impact; Novartis) or an isocaloric, isonitrogenous control diet (Boost; Mead-Johnson). Blood flow to the antrum, duodenum, jejunum, ileum, colon, liver, kidneys, and spleen was determined at baseline and 30, 60, 90, and 120 min after gavage.Baseline blood flows to the left and right kidneys were within 10%, indicating the technical integrity of the microsphere technique and assay. Control diet augmented blood flow compared to IED in the antrum, duodenum, jejunum, and spleen. Conversely, IED gavage stimulated a delayed and sustained hyperemic response in the ileum. IED also increased hepatic blood flow early (30 min). IED increased blood glucose levels compared to control diet at 30, 60, and 90 min, suggesting enhanced nutrient absorption.These data show that blood flow distribution depends on nutrient composition and that IED preferentially augments blood flow to the ileum. Since the terminal jejunum and ileum contain much of the GALT, our data suggest that a mechanism for enterally stimulated mucosal immunity involves selective perfusion of the terminal ileum during IED nutrient absorption.

Abstract

Facial fractures (FF) have been suggested to protect the brain from severe injury. However, others have stated that facial fractures are a marker for increased risk of brain injury. The aim of this study is to evaluate the association between facial fractures, brain injury, and functional outcome. A retrospective review of our prospective trauma database was performed for blunt trauma patients during a 7-year period (January 1993 through December 1999) at the University of Louisville Hospital. We identified 7324 blunt trauma patients at a Level 1 trauma center. Severity of head injury in patients with and without FF was compared. The severity of brain injury was evaluated by admission Glasgow Coma Score (GCS) as well as specific head, neck, cervical spine, and face Acute Injury Score (AIS). Length of intensive care unit (ICU) stay, hospital stay, and Functional Independence Measures (FIM) score were also identified. A total of 1068 (14.6%) patients were diagnosed with FF; of these 848 (79.4%) patients suffered some form of brain injury by CT abnormality, clinical examination, or both. A total of 2192 patients were treated for head injury without FF; 220 patients were treated for FF without head injury. FF with traumatic brain injury (TBI) were found to occur significantly greater than FFs without TBI (P < 0.001). The mean GCS on admission for FF with head injury was 12, which was similar to that of patients with head injury alone with a GCS of 10 but was significantly less than that of patients with FF alone with a GCS of 15 (P < 0.05). Injury Severity Score for patients with FF and head injury was significantly worse compared with patients with head injury alone and those with FF alone (P < 0.0001). Mean ICU stay and hospital stay were similar for all three groups (ranges 3-6 and 6-12 days); and were not significant (P < 0.06). FIM score was significantly lower for patients with FF and head injury compared with FF alone (P = 0.0003) and similar to that of patients with head injury. FF were found to have a significantly greater incidence of TBI. FF with TBI had a similar severity of head injury when compared with patients with head injury alone by demonstrating similar GCS, AIS of the head and neck, and early functional recovery. This analysis does not support the hypothesis that the face provides a protective effect for the brain and therefore leading to a more favorable short-term outcome. Thus patients with facial fractures should be treated with the same caution as patients with significant blunt head trauma.

Abstract

Hospital admission for an alcohol-related traumatic injury may offer a "teachable moment" to address a patient's alcohol problem. Although trauma teams provide a number of other health-related services, there may be characteristics of alcohol-positive victims that act as barriers toward providing alcohol counseling. The purpose of this study was to compare the characteristics and hospital outcomes of trauma patients who tested positive for alcohol at the time of hospital admission with those who did not. This information is useful for planning interventions and referrals for treatment.The study was a retrospective comparison of alcohol-positive and alcohol-negative patients who were admitted for at least 48 hours to a Level-I trauma center. Data from 1,049 trauma victims (736 male, 742 alcohol-negative) were abstracted from clinical records.Several characteristics were found to be associated with alcohol-related injuries: being male, aged 40 years or less, having a toxicology screen positive for illicit drugs, lacking health insurance, being indigent and sustaining an injury related to violence. Alcohol-positive patients were also found to spend fewer days in a critical care unit, to be less likely to die and to be less likely to be transferred to another hospital than alcohol-negative patients, despite having similar injury severity.Patient characteristics suggest that there are obstacles to providing interventions and referrals by healthcare professionals for victims of alcohol-related injuries. Less expensive options that consider the demographic features of this patient population need to be developed as an alternative to expensive, professional interventions.

Abstract

Early diagnosis, expeditious vascular repair, and aggressive management of complications have resulted in an amputation rate of less than 9%. Repair rather than ligation of an associated femoral vein injury is commonly practiced by experienced trauma surgeons. In most circumstances, a reversed autogenous saphenous vein graft from the contralateral extremity is the conduit of choice; however, if a saphenous vein cannot be used because of size discrepancies, multiple associated trauma, or extensive contamination, polytetrafluoroethylene can be used with good results. If vein ligation is performed, early fasciotomy is indicated for close and meticulous monitoring of the compartmental pressures. Clearly, the most crucial components for a successful outcome are a thorough evaluation, early operation, and a flawless vascular repair.

Abstract

Although the use of stapling devices in elective colon surgery has been shown to be as safe as handsewn techniques, there have been concerns about their safety in emergency trauma surgery. The purpose of this study was to compare stapled with handsewn colonic anastomosis following penetrating trauma.This was a prospective multicenter study and included patients who underwent colon resection and anastomosis following penetrating trauma. Multivariate logistic regression analysis was used to identify independent risk factors for abdominal complications and compare outcomes between stapled and handsewn repairs.Two hundred seven patients underwent colon resection and primary anastomosis. In 128 patients (61.8%) the anastomosis was performed with handsewing and in the remaining 79 (38.2%) with stapling devices. There were no colon-related deaths and the overall incidence of colon-related abdominal complications was 22.7% (26.6% in the stapled group and 20.3% in the handsewn group, p = 0.30). The incidence of anastomotic leak was 6.3% in the stapled group and 7.8% in the handsewn group (p = 0.69). Multivariate analysis adjusting for blood transfusions, fecal contamination, and type of antibiotic prophylaxis showed that the adjusted odds ratio (OR) of complications in the stapled group was 0.83 (95% CI, 0.38-1.74, p = 0.63). In a second multivariate analysis adjusting for blood transfusions, hypotension, fecal contamination, Penetrating Abdominal Trauma Index, and preoperative delays the adjusted OR in the stapled group was 0.99 (95% CI, 0.46-2.11, p = 0.99).The results of this study suggest that the method of anastomosis following colon resection for penetrating trauma does not affect the incidence of abdominal complications and the choice should be surgeon's preference.

Abstract

Clinical pathways (CPs) have been shown to be beneficial in optimizing patient care and resource use.A multidisciplinary CP for the treatment of severe traumatic brain injury (Glasgow Coma Scale score of 3-7) was developed. Data from these patients (group I) were collected prospectively and compared with a retrospective database (group II).There were a total of 119 patients managed in conjunction with the CP and 43 patients in the control group. No statistical differences were found between the groups in age, Glasgow Coma Scale score at 24 hours, or Injury Severity Scores. There was a significant decrease in the length of hospital stay, intensive care unit stay, and length of ventilator support in the study group (group I: 22.5, 16.8, and 11.5 days, respectively; group II: 31.0, 21.2, and 14.4 days, respectively; p < 0.03).The use of this CP helped to standardize and improve patient care with fewer complications and a potential cost savings of approximately $14,000 per patient.

Abstract

The factors contributing to a higher mortality rate in elderly thermal injury victims are not well delineated. The purpose of this study is to determine the impact of the initial injury, medical comorbidities, and burn size on patient outcome and to determine a level of injury in this population when comfort care is an appropriate first choice. Individual medical records of patients over 65 years of age admitted to our burn center over a 10-year interval were reviewed for patient demographics, mechanism of injury, total body surface area (TBSA) burned, medical comorbidities, use of Swan-Ganz catheters, evidence of inhalation injury, level of support, and patient outcome. The mechanisms of thermal injury were flame (68%), scald (21%) and electrical or chemical contact (11%). Twenty-six preventable bathing, cooking, and smoking-related injuries were seen (33%). The average TBSA was 25 per cent. Average length of stay varied depending on outcome. The overall mortality rate for this group was 45 per cent. Patients older than 80 years with 40 per cent or greater TBSA burned had a 100 per cent mortality rate despite aggressive treatment. Burn wound size correlated better with probability of poor outcome than age. Thermal injuries in the elderly are becoming more important with the aging of our population. Underlying medical problems--specifically chronic obstructive pulmonary disease--do play a role in increased patient morbidity and mortality. This study shows that age greater than 80 years in combination with burns greater than 40 per cent TBSA are uniformly fatal despite aggressive therapy. We believe that delaying the start of comfort-only measures in this situation only prolongs the pain and suffering for the patient, the family, and the physician.

Abstract

Chronic sepsis leads to an impaired intestinal microcirculation, which might reflect altered microvascular control. We hypothesized that intestinal microvascular sensitivity to norepinephrine (NE) is decreased during chronic sepsis. Chronic sepsis was induced by a polymicrobial inoculation of implanted subcutaneous sponges in rats. Septic rats were studied either 24 or 72 h after a single inoculation (1-hit) of bacteria. Other rats received a second inoculation (2-hit) of bacteria 48 h later and were studied at 24 h after the second inoculation. NE (0.01-1.0 microM) responses in the non-absorbing terminal ileal arterioles (inflow A1, proximal-p and distal-d premucosal A3) were measured by video microscopy. NE threshold sensitivity (pD(T20) = -log of 20% response dose) was analyzed. pD(T20) was significantly decreased in A1, pA3, and dA3 of 1-hit 24-h septic rats (P < 0.05), and was further decreased in all vessels of 2-hit 72-h septic rats (P < 0.05). In contrast, the pDT(T20) of all three vessels significantly returned toward normal values after 72 h in rats that had only 1 bacteria inoculation. We conclude that an initial bacterial challenge decreases vasoconstrictor reactivity of the intestinal microcirculation and that subsequent repeated bacterial challenge exacerbates this defect in vasoconstrictor control in the non-absorbing intestine.

Abstract

The authors have developed a clinical pathway for the treatment of spinal cord injuries to help improve patient care. A clinical pathway for the treatment of patients with spinal cord injury was developed through a multidisciplinary approach. The control group (group 1) consisted of patients who were treated in the 2 years before the initiation of the pathway. Data from patients treated in conjunction with this pathway were collected prospectively (group 2). Thirty-six patients were treated in conjunction with the pathway compared with 22 in the control group. Group 2 had 6.8 fewer intensive care unit days, 11.5 fewer hospital days, 6 fewer ventilator days (p < 0.05), and a lower rate of complications. The use of a clinical care pathway for spinal cord injuries has resulted in improved patient care and fewer complications.

Abstract

The use of ultrasonography and nonoperative management of solid organ injury has become standard practice in many trauma centers. Little is known about the effects of these changes on resident educational experience.We retrospectively reviewed resident evaluation of abdominal trauma and trauma operative experience as reported to the residency review committee between 1994 and 1999.A total of 4,052 patients underwent one or more of three diagnostic modalities. The nontherapeutic laparotomy rate as a result of positive diagnostic peritoneal lavages decreased from 35% to 14%. Although resident operative trauma experience was stable because of increases in operative burns and nonabdominal trauma, the number of abdominal procedures declined.Noninvasive diagnostic tests have allowed more rapid trauma evaluation and fewer nontherapeutic laparotomies. As nonoperative experience grows, the opportunity for operative experience decreases. These trends may adversely affect the education of residents and suggest that novel approaches are needed to ensure adequate operative experience in trauma.

Abstract

The management of colon injuries that require resection is an unresolved issue because the existing practices are derived mainly from class III evidence. Because of the inability of any single trauma center to accumulate enough cases for meaningful statistical analysis, a multicenter prospective study was performed to compare primary anastomosis with diversion and identify the risk factors for colon-related abdominal complications.This was a prospective study from 19 trauma centers and included patients with colon resection because of penetrating trauma, who survived at least 72 hours. Multivariate logistic regression analysis was used to compare outcomes in patients with primary anastomosis or diversion and identify independent risk factors for the development of abdominal complications.Two hundred ninety-seven patients fulfilled the criteria for inclusion and analysis. Overall, 197 patients (66.3%) were managed by primary anastomosis and 100 (33.7%) by diversion. The overall colon-related mortality was 1.3% (four deaths in the diversion group, no deaths in the primary anastomosis group, p = 0.012). Colon-related abdominal complications occurred in 24% of all patients (primary repair, 22%; diversion, 27%; p = 0.373). Multivariate analysis including all potential risk factors with p values < 0.2 identified three independent risk factors for abdominal complications: severe fecal contamination, transfusion of > or = 4 units of blood within the first 24 hours, and single-agent antibiotic prophylaxis. The type of colon management was not found to be a risk factor. Comparison of primary anastomosis with diversion using multivariate analysis adjusting for the above three identified risk factors or the risk factors previously described in the literature (shock at admission, delay > 6 hours to operating room, penetrating abdominal trauma index > 25, severe fecal contamination, and transfusion of > 6 units blood) showed no statistically significant difference in outcome. Similarly, multivariate analysis and comparison of the two methods of colon management in high-risk patients showed no difference in outcome.The surgical method of colon management after resection for penetrating trauma does not affect the incidence of abdominal complications, irrespective of associated risk factors. Severe fecal contamination, transfusion of > or = 4 units of blood within the first 24 hours, and single-agent antibiotic prophylaxis are independent risk factors for abdominal complications. In view of these findings, the reduced quality of life, and the need for a subsequent operation in colostomy patients, primary anastomosis should be considered in all such patients.

Abstract

Clinical pathways have been proven to be valuable tools in improving outcomes in patients with neurological diagnoses. However, their use with trauma populations has been limited. The unpredictable nature of trauma makes it difficult to develop a day-by-day plan of care that would be applicable to all patients with the same trauma diagnosis. Nevertheless, a severe traumatic brain injury (TBI) clinical pathway was developed and implemented at a Level 1 Trauma Center with significant reductions in length of stay and number of ventilator days. With the publication of the Guidelines for the Management of Severe Head Injury, this pathway was refashioned into a severe TBI phased-outcome pathway. Rather than a day-by-day plan of care, this clinical pathway consists of four phases of care: (a) admission to the intensive care unit, (b) acute critical care, (c) mobility and weaning, and (d) pre-rehabilitation. After 12 months, the improvements accomplished by the original pathway have been maintained or exceeded.

Abstract

The frequency of women who have sustained severe injuries has increased over the past 30 years. The purpose of this study was to evaluate whether severely injured women have a survival advantage over men. To address this issue, we undertook a multicenter evaluation of the effects of gender dimorphism on survival in trauma patients.Patient information was collected from the databases of three level I trauma centers. We included all consecutive patients who were admitted to these centers over a 4-year period. We evaluated the effects of age, gender, mechanism of injury, pattern of injury, Abbreviated Injury Score (AIS), and Injury Severity Score (ISS) on survival.A total of 20,261 patients were admitted to the three trauma centers. Women who were younger than 50 years of age (mortality rate 5%) experienced a survival advantage over men (mortality rate 7%) of equal age (odds ratio 1.27, P <0.002). This advantage was most notably found in the more severely injured (ISS >25) group (mortality rate 28% in women versus 33% in men). This difference was not attributable to mechanism of injury, severity of injury, or pattern of injury.Severely injured women younger than 50 years of age have a survival advantage when compared with men of equal age and injury severity. Young men have a 27% greater chance of dying than women after trauma. We conclude that gender dimorphism affects the survival of patients after trauma.

Abstract

Nonoperative management is now regarded as the best alternative for the treatment of patients with complex blunt liver injuries. However, some patients still require surgical treatment for complications that were formerly managed with laparotomy and a combination of image-guided studies.We reviewed the medical records of 15 patients who had complex blunt liver injuries that were managed nonoperatively and in which biliary peritonitis developed.Delayed laparoscopy was performed 2-9 days after admission in patients with extensive liver injuries. All 15 patients had developed local signs of peritonitis or a systemic inflammatory response. Laparoscopy was indicated to drain a large retained hemoperitoneum (eight patients), bile peritonitis (four patients), or an infected perihepatic collection (three patients). Laparoscopy was successful in all patients, and there was no need for further interventions.The data indicate that as more patients with complex liver injuries are treated nonoperatively and the criteria for nonoperative management continue to expand, more patients will need some type of interventional procedure to treat complications that historically were managed by laparotomy. At this point, laparoscopy is an excellent alternative that should become part of the armamentarium of the trauma surgeons who treat these patients.

Abstract

Our aim was to evaluate the impact of cell-saver volume and free hemoglobin load on renal dysfunction. Intraoperative blood salvage was conducted in standard fashion, and in each case a sample of the blood was removed for testing. Outcome data on individual patients were collected during a 6-year period (1992-1998). The total amount of free hemoglobin each patient received was calculated. Renal dysfunction was defined as a rise in creatinine level of 1.0 mg/dL above baseline. There were a total of 125 patients who received salvaged blood. The free hemoglobin concentration ranged from 19 to 304 mg/dL (mean, 87.5 mg/dL). Patients were stratified into groups on the basis of the total free hemoglobin received, and the Kruskal-Wallis test demonstrated a difference between groups in the prevalence of renal dysfunction (P < 0.001). A total of 15 patients (12%) had significant postoperative renal dysfunction. There was an association between the amount of free hemoglobin load and subsequent renal dysfunction. This may warrant further study toward establishing policies and limits regarding maximal free hemoglobin blood.

Abstract

Altered intestinal blood flow during systemic inflammation leads to organ dysfunction. Mucosal ischemia occurs during sepsis despite an increase in portal blood flow. We hypothesized that separate mechanisms are active in the large resistance and small mucosal microvessels to account for this dichotomy.Chronic infection was induced in rats by bacterial inoculation (Escherichia coli and Bacteroides fragilis) of an implanted subcutaneous sponge. Separate groups were studied at 24 and 72 hours after a single inoculation of bacterium or 24 hours after a second inoculation (ie, 72 hours of sepsis). Time-matched controls were used for each group. Intravital microscopy of the terminal ileum was used to assess endothelial-dependent vasodilation to acetylcholine (10(-9) to 10(-5) mol/L) in resistance (A(1)) and premucosal (A(3)) arterioles. Threshold sensitivity (-log of 20% response dose) was calculated from dose response curves for each animal.Vasodilator sensitivity to acetylcholine in A(1) arterioles was significantly decreased at 24 hours, and these changes persisted up to 72 hours after a single bacterial inoculation. There was no change in the dilator sensitivity of A(3) arterioles after a single inoculation. When there was a challenge with a second bacterial inoculation, there was a reversal of the A(1) dilator response and an increase in A(3) sensitivity.An initial septic event results in a decrease in dilator reactivity in the resistance A1 arterioles that persists for at least 72 hours. A sustained septic challenge results in increased dilator reactivity in both A(1) and A(3) vessels. This enhanced sensitivity during sepsis suggests that more than 1 therapeutic approach to preservation of intestinal blood flow will be necessary.

Abstract

Early sepsis leads to renal hypoperfusion, despite a hyperdynamic systemic circulation. It is thought that failure of local control of the renal microcirculation leads to hypoperfusion and organ dysfunction. Of the many mediators implicated in the pathogenesis of microvascular vasoconstriction, arachidonic acid metabolites are thought to be important. Vasoconstriction may be due to excess production of vasoconstrictors or loss of vasodilators. Using the isolated perfused kidney model, we describe a sepsis-induced rise in renal vascular resistance and increased production of key arachidonic acid metabolites, both vasoconstrictors and vasodilators, suggesting excessive production of vasoconstrictors as a cause for microcirculatory hypoperfusion. There is evidence of increased enzymatic production of arachidonic acid metabolites as well as nonenzymatic, free radical, catalyzed conversion of arachidonic acid. Pentoxifylline (a phosphodiesterase inhibitor) and U74389G (an antioxidant) both have a protective effect on the renal microcirculation during sepsis. Both drugs appear to alter the renal microvascular response to sepsis by altering renal arachidonic acid metabolism. This study demonstrates that sepsis leads to increased renal vascular resistance. This response is in part mediated by metabolites produced by metabolism of arachidonic acid within the kidney. The ability of drugs to modulate arachidonic acid metabolism and so alter the renal response to sepsis suggests a possible role for these agents in protecting the renal microcirculation during sepsis.

Abstract

To define the changes in demographics of liver injury during the past 25 years and to document the impact of treatment changes on death rates.No study has presented a long-term review of a large series of hepatic injuries, documenting the effect of treatment changes on outcome. A 25-year review from a concurrently collected database of liver injuries documented changes in treatment and outcome.A database of hepatic injuries from 1975 to 1999 was studied for changes in demographics, treatment patterns, and outcome. Factors potentially responsible for outcome differences were examined.A total of 1,842 liver injuries were treated. Blunt injuries have dramatically increased; the proportion of major injuries is approximately 16% annually. Nonsurgical therapy is now used in more than 80% of blunt injuries. The death rates from both blunt and penetrating trauma have improved significantly through each successive decade of the study. The improved death rates are due to decreased death from hemorrhage. Factors responsible include fewer major venous injuries requiring surgery, improved outcome with vein injuries, better results with packing, and effective arterial hemorrhage control with arteriographic embolization.The treatment and outcome of liver injuries have changed dramatically in 25 years. Multiple modes of therapy are available for hemorrhage control, which has improved outcome.

Abstract

Criteria for trauma team activation are continually being evaluated to ensure proper utilization of resources. We examined the impact of prehospital (PH) hypotension (systolic blood pressure < or = 90) on outcome (operative intervention and mortality) and its usefulness as an indicator for trauma team activation.A database was created by using the trauma registry for all nonburned, injured patients from July of 1993 through October of 1998 at our Level I trauma center.Of 6,976 patients (83% blunt injury) in the database, 4,437 had a PH blood pressure recorded. Documented PH hypotension was present in 791 patients. Hypotension persisted in the emergency department (ED) in 299 patients, but 193 of them showed minimal or no signs of life on arrival. Four hundred ninety-two patients had PH hypotension but normal ED systolic blood pressure, and 130 patients developed ED hypotension after normal PH systolic blood pressure. Nearly half of the patients with hypotension were taken from the ED directly to the operating room primarily for hemorrhage control procedures. The early and late mortality rates of patients with PH and ED hypotension were 12% and 32%, respectively. Other PH interventions had minimal effect on mortality in the hypotensive patient.Prehospital hypotension remains a valid indicator for trauma team activation. Even though most of the non-DOA patients (492 of 598) were stable on arrival to the ED, nearly 50% required operative intervention, and an additional 25% required intensive care unit admission. The trauma team should be activated and involved with these patients early.

Abstract

Multiple factors contribute to the development of posttraumatic empyema. These factors include the conditions under which the tube is inserted (emergent or urgent), the mechanism of injury, retained hemothorax, and ventilator care. The incidence of empyema in placebo groups ranges between 0 and 18%. The administration of antibiotics for longer than 24 hours did not seem to significantly reduce this risk compared with a shorter duration, although the numbers in each series were small. Most reports found a significant reduction in pneumonitis when patients received prolonged prophylactic antibiotics. This use of antibiotics might possibly be better described as presumptive therapy rather than prophylactic.

Abstract

Many trauma centers have separated emergency and general surgery from trauma care. However, decreased trauma volume and more frequent nonoperative management may limit operative experience and the economic viability of the trauma service. Trauma surgeons at our Level I trauma center have long provided all emergency surgical care and elective surgery. We sought to determine the impact of this policy.We reviewed all admissions to the trauma service from June of 1992 to July of 1998 and cross-referenced this with our trauma registry. The number of major and minor procedures performed was also determined, and we reviewed all operative procedures by the trauma service for June of 1996 to October of 1998.Total admissions by the trauma service averaged 3,003 patients/year (range, 2,798-3,198 patients). Nontrauma patients accounted for 34% of all trauma service admissions (range, 26-40%). During this time period, there was no change in volume of operative or intensive care unit procedures, whereas minor procedures recently decreased from a peak of 141/month to 50/month. This was largely due to decreased use of diagnostic peritoneal lavage (surgeon reimbursable) and an increased use of computed tomographic scan and ultrasound (not presently reimbursed) to evaluate blunt abdominal trauma. During the past 2 years, nontrauma cases accounted for 33% of all operative procedures by the trauma service.Maintenance of emergency and general surgical care by the trauma service has allowed us to buffer impact of variations in trauma volume and to maintain operative skills in an era of increased nonoperative management of many injuries.

Abstract

Delayed gastric emptying following traumatic brain injury (TBI) has led some to advocate jejunal feeding. Our purpose was to review our experience with percutaneous endoscopic gastrostomy (PEG) and intragastric feeding in TBI patients to assess safety and effectiveness.All patients on a TBI clinical pathway at our institution were targeted for early PEG. After PEG, standard enteral nutrition was initiated. Abdominal examination and gastric residual volumes were used to assess tolerance.There were 118 patients with moderate to severe TBI. The average age was 36 years. Mean Injury Severity Score (ISS) was 25. Enteral access was obtained and intragastric feeding was initiated on day 3. 6. Intragastric feeding was tolerated without complication in 111 of 114 (97%) patients. Five patients aspirated, but had no evidence of intolerance prior to the event.PEG provided reliable enteral access in moderate to severe TBI patients. Intragastric feeding was well tolerated with a low complication rate (4%).

Abstract

Respiratory failure is a common complication among patients sustaining major blunt trauma. This is usually due to the underlying pulmonary injury, pneumonia, or adult respiratory distress syndrome. However, we have frequently found these patients to actually have a pleural process as the cause of their respiratory failure. Our objective was to assess the frequency of empyema and restrictive pleural processes after blunt trauma and their contribution to respiratory failure. We retrospectively reviewed all blunt trauma patients over a 5-year period who required a thoracotomy and decortication for empyema. Twenty-eight patients with blunt trauma required a thoracotomy and decortication for empyema. The most common finding was infected, loculated hemothorax/effusion in 23 patients, whereas 5 had an associated pneumonia. Chest radiographs were nondiscriminating, whereas CT scans in 25 patients showed previously unrecognized fluid collections, air-fluid levels, or gas bubbles. Neither thoracentesis nor placement of additional chest tubes was helpful. Positive cultures were uncommon. Ventilator dependence was present preoperatively in 13 patients who were on the ventilator an average of 13 days preoperatively and only 5.8 days postoperatively. Several patients believed to have adult respiratory distress syndrome were weaned within 72 hours of operation. All patients were ultimately cured. Empyema is an under-recognized complication of blunt trauma and may contribute to respiratory failure and ventilator dependence. Although difficult to diagnose, empyema should be considered in blunt trauma patients with respiratory failure and an abnormal chest radiograph. CT aids in the diagnosis, and the results of surgical treatment are excellent.

Abstract

Fournier's disease is a potentially fatal acute, gangrenous infection of the scrotum, penis, or perineum associated with a synergistic bacterial infection of the subcutaneous fat and superficial fascia. Thrombosis of small subcutaneous arterioles with resultant ischemia contributes to the rapid extension of the infection. During a 12-year period, the clinical and operative records of 14 patients with Fournier's gangrene were analyzed. All patients were treated with broad spectrum antibiotics and serial surgical debridements. Nine patients had polymicrobial isolates from the initial wound culture; two patients had Group A Streptococcus species as the sole isolate. The etiology of the infection was identified in 12 patients. Five patients died for an overall mortality of 38 per cent. The mean age of survivors was 51 years compared with 75 years for nonsurvivors (P<0.05). The last six patients in this series survived. The mean hospital stay was 29 days. Four patients (31%) had a prior history of diabetes; however, 11 patients (85%) had elevated serum glucose levels (>120 mg/dL) on admission. All patients were hypoalbuminemic on admission. Survivors had an average serum creatinine on admission of 1.28 mg/dL compared with 3.1 mg/dL for nonsurvivors. Although supportive care is required in these patients, the mainstay for treatment of Fournier's gangrene entails an aggressive approach with frequent and extensive soft tissue debridements to control the invasive nature of the infection with delayed wound coverage once the infection has been controlled. Elderly patients with evidence of renal dysfunction on admission have a poor prognosis despite aggressive therapy.

Abstract

Numerous factors may impede the delivery of enteral tube feedings (ETF) in the intensive care unit (ICU). We designed a prospective study to determine whether the use of an infusion protocol could improve the delivery of ETF in the ICU.In a prior prospective study, we monitored all patients admitted to the medical intensive care unit (MICU) or cardiac care unit (CCU) who were made nil per os and placed on ETF (control group). We found that critically ill patients received only 52% of their goal calories, primarily due to physician underordering (66% of goal), frequent cessations of ETF (22% of the time), and slow advancement (14% at goal by 72 hours). Based on these findings, we developed an ETF protocol that incorporated standardized physician ordering and nursing procedures, rapid advancement, and limited ETF interruption. After extensive educational sessions, the ETF protocol was begun. Again, all patients admitted to the MICU or CCU who were made nil per os and placed on ETF were prospectively followed (protocol group).Thirty-one patients in the protocol group were followed during 312 days of ETF and compared with the control group (44 patients with 339 days of ETF). Despite efforts by the nutritional support team, the infusion protocol was used in only 18 patients (58%). The main reasons for noncompliance with the protocol were physician preference and system failure (ETF order sheet not placed in chart). When used, the infusion protocol improved physician ordering (control 66% of goal volume, noncompliant 68%, compliant 82%, p < .05); delivery of calories (control 52% of goal, noncompliant 55%, compliant 68%, p < .05); and advancement of ETF (control 14% at goal by 72 hours, noncompliant 31%, compliant 56%, p < .05). Although significant reduction in ETF cessation due to nursing care was noted, it represented only a fraction of the total time ETF were stopped. Cessation due to residual volumes, patient tolerance, and procedure continued to be a frequent occurrence and was often avoidable.An evidence-based infusion protocol improved the delivery of ETF in the ICU, primarily because of better physician ordering and more rapid advancement. The nursing staff rapidly assimilated these changes. However, physicians' reluctance to use the protocol limited its efficacy and will need continued educational efforts.

Abstract

To evaluate those factors that impact on the delivery of enteral tube feeding.Prospective study.Medical intensive care units (ICU) and coronary care units at two university-based hospitals.Forty-four medical ICU/coronary care unit patients (mean age, 57.8 yrs; 70% male) who were to receive nothing by mouth and were placed on enteral tube feeding.Rate of enteral tube feeding ordered, actual volume delivered, patient position, residual volume, flush volume, presence of blue food coloring in oropharynx, and stool frequency were recorded every 4 hrs. Duration and reason for cessation of enteral tube feeding were documented.Physicians ordered a daily mean volume of enteral tube feeding that was 65.6% of goal requirements, but an average of only 78.1% of the volume ordered was actually infused. Thus, patients received a mean volume of enteral tube feeding for all 339 days of infusion that was 51.6% of goal (range, 15.1% to 87.1%). Only 14% of patients reached > or = 90% of goal feeding (for a single day) within 72 hrs of the start of enteral tube feeding infusion. Of 24 patients weighed before and after, 54% were noted to lose weight on enteral tube feeding. Declining albumin levels through the enteral tube feeding period correlated significantly with decreasing percent of goal calories infused (p = .042; r2 = .13). Diarrhea occurred in 23 patients (52.3%) for a mean 38.2% of enteral tube feeding days. In >1490 bedside evaluations, patients were observed to be in the supine position only 0.45%, residual volume of >200 mL was found 2.8%, and blue food coloring was found in the oropharynx 5.1% of the time. Despite this, cessation of enteral tube feeding occurred in 83.7% of patients for a mean 19.6% of the potential infusion time. Sixty-six percent of the enteral tube feeding cessations was judged to be attributable to avoidable causes.The current manner in which enteral tube feeding is delivered in the ICU results in grossly inadequate nutritional support. Barely one half of patient caloric requirements are met because of underordering by physicians and reduced delivery through frequent and often inappropriate cessation of feedings.

Abstract

The two-hit theory of multiple organ dysfunction syndrome proposes that an initial insult primes the host for an altered response to subsequent stimuli. We have previously documented enhanced dilator tone in the small intestine after a two-hit insult; however, the effects on vasoconstrictor function are unknown. We postulated that prior hemorrhage and resuscitation followed by bacteremia would alter microvascular responsiveness to alpha-adrenergic stimulation.Male Sprague-Dawley rats underwent fixed-volume hemorrhage with resuscitation (H/R) or sham procedure (Sham). At 24 or 72 h, in vivo videomicroscopy of the small intestine was performed (inflow A1 and premucosal A3 arterioles). Constrictor function was assessed by topical application of norepinephrine (NE; 10(-8)-10(-6) M) before and 1 h after intravenous Escherichia coli or saline.Sham, 24 or 72 h H/R, and E. coli alone produced no significant changes in A1 or A3 response to NE. Sequential H/R + E. coli resulted in decreased constrictor response in both A1 (72 h H/R + E. coli-38% from baseline vs Sham - 54%, P < 0.05) and A3 arterioles (-8% vs -51%, P < 0.05) at high doses of NE (10(-6) M).Prior H/R primes the intestinal microvasculature for an altered response during a subsequent stress and these effects persist for up to 72 h following H/R. Sequential insults in this two-hit model caused marked hyporesponsiveness to NE. These alterations in control of microvascular tone might contribute to the hemodynamic compromise of sepsis, impair mucosal blood flow, and contribute to the development of MODS.

Abstract

To evaluate the incidence, timing of diagnosis, clinical factors for adverse outcome, and role of anticoagulant, surgical therapy, or endovascular intervention for patients with blunt carotid artery injury (BCAI).Retrospective review of the records of patients who sustained BCAI between 1987 and 1997.There were 18 men and 12 women, with an average age of 29 years. The diagnosis of BCAI was initially suspected in 15 patients after a major or new neurologic event, and in 15 patients after changes were shown by computed tomography. BCAI was confirmed by arteriography in 29 patients and by magnetic resonance angiography in 1 patient. Treatment consisted of antiplatelet therapy (n = 9), anticoagulation (n = 8), surgical repair (n = 6), observation (n = 4), and endovascular embolization (n = 3). With some type of treatment, 14 patients with no neurologic deficits remained stable; however, treatment improved the final neurologic outcome in 8 patients (20%). Three patients remained with severe deficits, and five patients died.The consequences of BCAI may be devastating. In our study, there were no reliable means to suspect this injury before neurologic symptoms or abnormalities show on computed tomographic scan. Although external signs are occasionally helpful, most patients have no pattern of injury to suggest BCAI. For patients whose findings after neurologic examination do not correlate with those on the computed tomographic scan, an immediate angiogram is indicated. Occasionally, a proximal injury can be surgically repaired, but in most patients, anticoagulation therapy appears to be the best treatment to avoid or improve neurologic deficits.

Abstract

Postprandial intestinal hyperemia is a complex vascular response during nutrient absorption. Many mediators have been studied including enteric reflexes, GI hormones, and absorption-stimulated metabolic mediators such as pH and adenosine. We have shown that nitric oxide (NO) mediates premucosal arteriolar dilation during glucose absorption and that glucose-induced portal vein NO metabolite production requires adenosine A2b receptor activation. We hypothesize that Na+-linked absorption of l-glutamine or l-glycine might also stimulate NO release in the enteroportal circulation via adenosine A2b receptors.Male Sprague-Dawley rats (190-220 g) were anesthetized with urethane/alpha-chloralose and cannulated for hemodynamic monitoring and blood sampling. A right paramedian abdominal incision was made for access to both the stomach (gavage) and the portal vein (blood sampling). Animals received intragastric nutrient gavage (saline, d-glucose, l-glutamine, racemic glycine, or oleic acid) with and without adenosine A2b receptor blockade. NO metabolites (NOx) were measured by a fluorescent modified-Greiss assay at baseline and 30 min after nutrient gavage.Glucose and glutamine gavage increased portal NOx levels compared to baseline, while glycine and oleic acid gavage did not. Adenosine A2b antagonism returned NOx levels to baseline in both glucose and glutamine gavage animals, but did not alter portal NOx levels in glycine- or oleic acid-treated animals.These data suggest that nutrient-induced adenosine is involved in a signaling process from the intestinal epithelium to nitric oxide-producing cells elsewhere in the vasculature. Adenosine A2b receptors are required for NO production during Na+-linked glucose or glutamine absorption.

Abstract

Common and external iliac artery injuries associated with pelvic fractures are uncommon. The diagnosis of such injuries is based on clinical findings and confirmed by arteriography.Retrospective chart review.University Level I trauma center.Five men and three women, aged seventeen to seventy-six years, with injuries to the common and external iliac arteries associated with pelvic fractures.All patients sustained complex pelvic fractures associated with multiple blunt injuries. Five injuries occurred on the right side. Two patients had an associated right vertical shear pelvic fracture. In five patients, vascular injury was diagnosed in the first six hours after admission. One patient presented with an aneurysm of the right common iliac artery two months after his initial injury. All patients underwent surgical repair with an interposition graft, which failed in two patients, who underwent vascular reconstruction ten hours after the injury. One patient died of associated injuries.Arterial hyperextension with intimal damage seems to be the most likely cause of this injury. Ideally, an extraperitoneal approach should be attempted to minimize blood losses and, due to the size of the iliac vessels, an interposition graft should be used for reconstruction.

Abstract

Sepsis results in hyporesponsiveness to alpha-adrenergic stimulation. This is thought to be mediated by the release of vasoactive compounds from the septic endothelium or by the direct effect of sepsis on vascular smooth muscle (VSM) contractile mechanics and machinery. Previous studies have used lethal models of sepsis or endotoxemia to examine this phenomenon. The present study utilizes a clinically relevant, nonlethal model of soft tissue infection to determine the effects of sepsis on alpha-adrenergic mechanisms. We hypothesize that subacute sepsis causes impaired alpha-adrenergic vascular responsiveness by a combination of effects on adrenergic constrictor mechanisms, endogenous dilator tone, and VSM contractile function.Male Sprague-Dawley rats underwent implantation of a 2 x 2-cm2 gauze sponge into a subcutaneous pocket created at the base of the tail. Five days after implantation, sepsis (S) was induced by inoculation of the sponge with 10(9) CFU Escherichia coli and Bacteroides fragilis. Controls (C) were inoculated with saline. Thoracic aortic harvest was performed 24 and 48 h after sponge inoculation for organ bath ring studies. Receptor-mediated (phenylephrine) and nonreceptor-mediated (KCl) maximum force of contraction (Fmax) was measured. Vessel sensitivity (pD2) to phenylephrine, acetylcholine, and KCl was calculated from dose-response curves.At 24 h, sepsis resulted in a lower Fmax to phenylephrine (1.15 for C vs 0.5 for S, P < 0.05 by ANOVA), despite an increase in vessel sensitivity (pD2) to alpha-adrenergic stimulation (6.70 for C vs 6.88 for S, P < 0.05 by ANOVA). Fmax to KCl was lower in septic animals at 24 h (3. 50 for C vs 2.77 for S, P < 0.05 by ANOVA) and sensitivity to acetylcholine (pD2) was markedly increased (6.56 for C vs 7.23 for S, P < 0.05 by ANOVA). At 48 h, the impairment in Fmax to alpha-adrenergic stimulation (2.29 for C vs 1.72 for S, P < 0.05 by ANOVA) and KCl (3.5 for C vs 3.08 for S. P < 0.05 vs 24 h C by ANOVA) persisted without any change in sensitivity to phenylephrine or acetylcholine.Subacute sepsis results in an early suppression of maximum contractile force despite an increase in adrenergic receptor sensitivity (pD2). This may be secondary to an elevation in dilator sensitivity combined with a direct effect of sepsis on VSM contractile mechanisms. Later in the septic process, however, alpha-adrenergic hyporesponsiveness ( downward arrow Fmax) is primarily due to changes in VSM contractile machinery.

Abstract

Allowing a patient's nutritional state to deteriorate through the perioperative period adversely affects measureable outcome related to nosocomial infection, multiple organ dysfunction, wound healing, and functional recovery. Careful preoperative nutritional assessment should include a determination of the level of stress, an evaluation of the status of the GI tract, and the development of specific plans for securing enteral access. Patients already demonstrating compromise of nutritional status (defined by > 10% weight loss and serum albumin level < 2.5 g/dL) should be considered for a minimum of 7 to 10 days of nutritional repletion prior to surgery. Widespread use of total parenteral nutrition in unselected patients is unwarranted, may actually worsen outcome, and should be reserved for preoperative nutritional support only in severely malnourished patients in whom the GI tract is unavailable. Compared with the parenteral route, use of perioperative enteral feeding has been shown to provide more consistent and beneficial results, and can be expected to promote specific advantages in long-term morbidity and mortality.

Abstract

Nonoperative management has become the standard of care for hemodynamically stable patients with complex liver trauma. The benefits of such treatment may be obviated, though, by complications such as arteriovenous fistulas, bile leaks, intrahepatic or perihepatic abscesses, and abnormal communications between the vascular system and the biliary tree (hemobilia and bilhemia).We reviewed the hospital charts of 135 patients with blunt liver trauma who were treated nonoperatively between July 1995 and December 1997.Thirty-two patients (24%) developed complications that required additional interventional treatment. Procedures less invasive than celiotomy were often performed, including arteriography and selective embolization in 12 patients (37%), computed tomography-guided drainage of infected collections in 10 patients (31%), endoscopic retrograde cholangiopancreatography with endoscopic sphincterotomy and biliary endostenting in 8 patients (25%), and laparoscopy in 2 patients (7%). Overall, nonoperative interventional procedures were used successfully to treat these complications in 27 patients (85%).In hemodynamically stable patients with blunt liver trauma, nonoperative management is the current treatment of choice. In patients with severe liver injuries, however, complications are common. Most untoward outcomes can be successfully managed nonoperatively using alternative therapeutic options. Early use of these interventional procedures is advocated in the initial management of the complications of severe blunt liver trauma.

Abstract

Endothelial cell injury after hemorrhage and resuscitation (HEM/RES) might contribute to intestinal hypoperfusion and mucosal ischemia. Our recent work suggests that the injury might be the result of complement activation. We hypothesized that HEM/RES causes complement-mediated endothelial cell dysfunction in the small intestine.Male Sprague-Dawley rats (195-230 g) were anesthetized and HEM to 50% of baseline mean arterial pressure for 60 minutes. Just before RES, animals received either soluble complement receptor-1 (sCR1, 15 mg/kg) to inhibit complement activation or saline vehicle. Resuscitation was with shed blood and an equal volume of saline. Two hours after RES, the small bowel was harvested to evaluate intestinal nitric oxide synthase activity (NOS), neutrophil influx, histology, and oxidant injury.HEM/RES induced tissue injury, increased neutrophil influx, and reduced NOS activity by 50% (vs. SHAM), all of which were completely prevented by sCR1 administration. There were no observed differences in oxidant injury between the groups.Histologic tissue injury, increased neutrophil influx, and impaired NOS activity after HEM/RES were all prevented by complement inhibition. Direct oxidant injury did not seem to be a major contributor to these alterations. Complement inhibition after HEM might ameliorate reperfusion injury in the small intestine by protecting the endothelial cell, reducing neutrophil influx and preserving NOS function.

Abstract

The "two-hit" theory of multiple organ dysfunction (MOD) proposes that an initial insult, such as hemorrhage (HEM), primes the host for an abnormal response to a second stress such as infection. The immunologic/inflammatory component of this theory has been well examined; however, the effects on vascular responsiveness are poorly understood. We hypothesized that HEM primes the vasculature for an altered response to a second pathophysiologic stress.Male Sprague-Dawley rats underwent a fixed-volume HEM with resuscitation (H/R) or sham procedure (Sham). At 48 h, animals were given iv E. coli or saline and followed for 1 h. Thoracic aortic rings were then placed in organ baths containing Krebs buffer aerated with 95% O2, 5% CO2. Cumulative dose-response curves to phenylephrine (PHE) and acetylcholine (ACH) were obtained. Maximum force of contraction (Fmax) was measured and pD2 values (receptor sensitivity) were derived.H/R alone resulted in heightened constrictor tone and blunted dilator tone. E. coli reduced Fmax in response to PHE by 50% in Sham vs 76% in H/R. Receptor sensitivity (pD2) to PHE was reduced to a greater degree in H/R (3-fold vs 2-fold). These animals also had a more pronounced enhancement of ACH receptor sensitivity (7-fold vs 2-fold).Hemorrhage primes the vasculature for an altered response to a subsequent stress. When infection is added as a "second hit," responsiveness to adrenergic agents is diminished and dilator tone is increased. These data may explain the cardiovascular derangements seen clinically in patients who develop MODS after major hemorrhage followed sequentially by infection.

Abstract

Following resuscitation (RES) from hemorrhagic shock (HEM), intestinal microvessels develop progressive vasoconstriction that impairs mucosal blood flow, despite central hemodynamic RES. These events might have clinical consequences secondary to occult intestinal ischemia. We hypothesized that the microvascular impairments were due to progressive endothelial cell dysfunction and an associated reduction in the dilator, nitric oxide (NO), following HEM/RES. Male Sprague-Dawley rats, were monitored for central hemodynamics and the terminal ileum was studied with in vivo videomicroscopy. HEM was 50% of baseline mean arterial pressure (MAP) for 60 min, and RES was with shed blood + 1 volume of normal saline (NS). Following HEM/RES, acetylcholine (10)(-7), 10(-5) M) was topically applied and ileal inflow (A1) and premucosal arteriolar diameters were measured to assess endothelial-cell function at 60 and 120 min post-RES. Normalization of MAP, cardiac output, and heart rate demonstrated adequate systemic resuscitation. Post-RES vasoconstriction developed in A1 (-25%) and premucosal (-28%) arterioles with an associated reduction in A1 flow (-47%). However, there was a selective impairment of endothelial-dependent dilation that was manifested only in the smaller premucosal arterioles and not in the inflow, A1 arterioles. This suggests that multiple mechanisms are involved in the development of the post-RES vasoconstriction. The premucosal response was likely mediated by endothelial cell dysfunction, while the A1 response was probably the result of enhanced vasoconstrictor forces. This early microvascular dysfunction might contribute to the late sequelae of intestinal ischemia and might alter microvascular responses to subsequent systemic insults.

Abstract

Small intestine microvascular vasoconstriction and hypoperfusion develop after resuscitation (RES) from hemorrhage (HEM), despite restoration of central hemodynamics. The responsible mechanisms are unclear. We hypothesized that the microvascular impairment following HEM/RES was due to decreased intestinal microvascular nitric oxide (NO) production.Male Sprague-Dawley rats (195-230 g) were utilized and three experimental groups were studied: (1) SHAM (cannulated but no HEM), (2) HEM only, and (3) HEM/RES. HEM was to 50% of baseline mean arterial pressure for 60 min, and RES was with shed blood and an equivalent volume of saline. Ex vivo isolated intestinal perfusion and a fluorometric modification of the Greiss reaction were used to quantify production of NO metabolites (NOx). Perfusate von Willebrand factor (vWF) was used as an indirect marker of endothelial cell activation or injury. To assess the degree of NO scavenging by oxygen-derived free radicals, immunohistochemistry was used to detect nitrotyrosine formation in the intestine.Intestinal NOx decreased following HEM/RES (SHAM 1.35 +/- 0.2 mM vs HEM/RES 0.60 +/- 0.1 mM, P < 0.05), but not with HEM alone (1.09 +/- 0.3 mM). There were no differences in serum NOx levels between the three groups. Release of vWF was increased during the HEM period (SHAM 0.18 +/- 0.1 g/dl vs HEM 1.66 +/- 0.6 g/dl, P < 0.05). There was no detectable nitrotyrosine formation in any group.Intestinal NO metabolites decrease following HEM/RES. Elevated vWF levels during HEM and the lack of detectable nitrotyrosine suggest that this is due to decreased endothelial cell production of NO. HEM/RES-induced endothelial cell dysfunction may contribute to persistent small intestine post-RES hypoperfusion and vasoconstriction.

Abstract

The usefulness of clinical pathways for the complex trauma patient is unclear. We analyzed the effect of a clinical pathway for severe traumatic brain injury (TBI) on resource utilization.A clinical pathway for severe TBI (Glasgow Coma Scale (GCS) score < or = 8 at 24 hours) was developed by a multidisciplinary team and used for all patients with severe TBI. Data were gathered prospectively for 15 months and compared with data from historical controls from the previous year. Patients who survived < 48 hours were excluded.The clinical pathway was used for 84 patients with severe TBI and compared with 49 historical controls. No differences in Injury Severity Scores (27 vs. 27) or GCS scores at 24 hours (6.2 vs. 6.5) existed between control or pathway patients. There was an overall increase in the mortality rate of pathway patients (from 12.2 to 21.4%), but this was entirely attributable to withdrawal of care that was initiated by family members in patients with an average age of 71 years, an average GCS score of 4.7, and an average Injury Severity Score of 29. Among survivors, pathway patients had a significant decrease in ventilator days (11.5 +/- 0.9 vs. 14.6 +/- 1.2; p < 0.05), intensive care unit days (16.7 +/- 1.0 vs. 21.2 +/- 1.4; p < 0.05), and hospital days (23.4 +/- 1.2 vs. 31.0 +/- 3.0; p < 0.05). There were no differences in the incidence of complications or functional outcomes.The use of a clinical pathway for severe TBI resulted in a significant reduction in resource utilization. This study suggests that clinical pathways may be a useful component of patient care after blunt trauma.

Abstract

Patients with severe pancreatitis, characterized by multiple organ failure and pancreatic necrosis on CT scan (identified by an Acute Physiology and Chronic Health Evaluation II score of > or = 10 with > or = 3 Ranson criteria), most likely require aggressive nutritional support. Use of the enteral route of feeding may help contain the hypermetabolic stress response, reduce morphologic change and atrophy of the gut, and theoretically decrease late complications of nosocomial infection and organ failure. Evidence that decreasing degrees of stimulation of the pancreas occur as the site of feeding descends in the gastrointestinal tract and evidence from perspective, randomized trials suggest that jejunal feeding appears at least as safe and well tolerated as total parenteral nutrition in acute pancreatitis.

Abstract

The objective was to determine intestinal microvascular endothelial cell control after sequential hemorrhage and bacteremia.Sepsis that follows severe hemorrhagic shock often results in multiple system organ failure (MSOF) and death. The sequential nature of this clinical scenario has led to the idea of a "two-hit" theory for the development of MSOF, the hallmark of which is peripheral vasodilation and acidosis. Acute bacteremia alone results in persistent intestinal vasoconstriction and mucosal hypoperfusion. Little experimental data exist to support the pathogenesis of vascular dysregulation during sequential physiologic insults. We postulate that hemorrhagic shock followed by bacteremia results in altered microvascular endothelial cell control of dilation and blood flow.Rats underwent volume hemorrhage and resuscitation. A sham group underwent the vascular cannulation without hemorrhage and resuscitation, and controls had no surgical manipulation. After 24 and 72 hours, the small intestine microcirculation was visualized by in vivo videomicroscopy. Mean arterial pressure, heart rate, arteriolar diameters, and A1 flow by Doppler velocimetry were measured. Endothelial-dependent dilator function was determined by the topical application of acetylcholine (ACh). After 1 hour of Escherichia coil bacteremia, ACh dose responses were again measured. Topical nitroprusside was then applied to assess direct smooth muscle dilation (endothelial-independent dilator function) in all groups. Vascular reactivity to ACh was compared among the groups.Acute bacteremia, with or without prior hemorrhage, caused significant large-caliber A1 arteriolar constriction with a concomitant decrease in blood flow. This constriction was blunted at 24 hours after hemorrhage but was restored to control values by 72 hours. There was a reversal of the response to bacteremia in the premucosal A3 vessels, with a marked dilation both at 24 and 72 hours. The sequence of hemorrhage and E. coli resulted in a progressive enhanced reactivity to the endothelial-dependent stimulus of ACh in the A3 vessels at 24 and 72 hours. Reactivity to endothelial-independent smooth muscle relaxation and subsequent vessel dilation was similar for all groups.These data indicate that there is altered endothelial control of the intestinal microvasculature after hemorrhage in favor of enhanced dilator mechanisms in premucosal vessels with enhanced constrictor forces in inflow vessels. This enhanced dilator sensitivity is most evident in small premucosal vessels. This experimental finding supports the premise that an initial pathophysiologic stress alters the subsequent microvascular blood flow responses to systemic inflammation. These changes in the intestinal microcirculation are in concert with the "two-hit" theory for MSOF.

Abstract

Multiple-trauma patients are at increased risk for deep venous thrombosis (DVT) but are also at increased risk of bleeding, and the use of heparin may be contraindicated. Sequential pneumatic compression devices (SCDs) are an alternative for DVT prophylaxis. However, lower extremity fracture or soft tissue injury may preclude their use. In these circumstances, foot pumps (FPs) are often substituted, yet little clinical data exist to support their use. We identified 184 consecutive high-risk trauma patients who received DVT prophylaxis with compression devices. We reviewed demographic data, mechanism of injury, Injury Severity Score, injury pattern, and method of prophylaxis. Generally, SCDs were preferred, but FPs were substituted in patients with lower extremity injuries. Occurrences of DVT or pulmonary embolism were also noted. Patients surviving less than 48 hours were excluded. SCDs were used in 118 patients (64%) and FPs in 66 patients (34%). There were no differences in age, Injury Severity Score, or presence of shock on admission. As expected, FP patients were more likely to have lower extremity fractures (65 vs 26%; P < 0.05) and were also more likely to have associated pelvic fracture (59 vs 25%; P < 0.05) and chest injury (61 vs 26%, P < 0.05). There was no difference in the incidence of head injury, although SCD patients had more severe head injuries (Glasgow Coma Score, 7.9 vs 10.5; P < 0.05). The overall incidence of DVT was 5.4 per cent (10 of 184), with no differences between the two groups (SCD 7% vs FP 3%). Three patients had a pulmonary embolism (FP, two; SCD, one), none of which were fatal. Compression devices provide adequate DVT prophylaxis with a low failure rate (3-8%) and no device-related complications. FPs appear to be a reasonable alternative in the high-risk trauma patient when lower extremity fractures precludes use of SCD.

Abstract

Persistent posttraumatic pneumothorax (PPP) is an uncommon complication of traumatic injuries of the chest, usually managed with suction drainage and involving prolonged hospital stays. This study was conducted to assess the advantages of using video-assisted thoracoscopic surgery (VATS) in the management of patients with PPP.Eleven patients with PPP underwent VATS for diagnosis and for definitive treatment.Before VATS was done, all patients had undergone multiple attempts to resolve the PPP; the hospital stay before VATS was 10 days (range, 4-14 days). In 10 patients, the cause of the PPP was identified and a segmental stapled resection was performed, with complete success in resolving the air leak and obtaining pleural synthesis. In another patient, the source of the air leak was not identified and a thoracoscopically assisted chemical pleurodesis was performed, with immediate cessation of the air leak. All chest tubes were removed within 48 hours of the procedure; 9 patients were discharged within 72 hours of VATS. Preoperative computed tomography of the chest was useful in 2 patients, but bronchoscopy did not disclose any major airway injury.Videothoracoscopy is an accurate, safe, and reliable alternative to an open thoracotomy in the management of patients with PPP. In the patients in whom the procedure was completed, excellent results were obtained and the hospital stay was reduced. We believe that VATS should be used earlier and more frequently after failure of conservative management in such patients.

Abstract

The high mortality and morbidity rates after iliac vessel injuries remain a challenging problem for trauma surgeons. Several controversial issues surround the management of iliac vessel injuries, including the value of abbreviated laparotomy, the role of extra-anatomic bypass reconstruction (EABR), the use of vascular prostheses in the presence of contamination, and the need and timing for fasciotomy.Retrospective review of the records of patients who sustained an injury to the iliac vessel between 1987 and 1996.A total of 64 patients were treated, including 23 with isolated iliac vein injuries, 17 with arterial injuries, and 24 with combined arteriovenous injuries. Vascular prostheses were placed in 17 patients with arterial injuries, including 12 with associated intestinal wounds. Graft infection did not occur. Of the 24 patients with combined injuries, 11 underwent abbreviated laparotomy and 1 died. Five deaths, however, occurred in 13 patients in whom no attempts were made for damage control laparotomy. Significant differences between survivors and nonsurvivors included final arterial pH, final prothrombin time, length of hypotension, and number of transfusions. Arterial ligation with EABR was performed in five patients and failed in two. Deep venous thrombosis and pulmonary embolism occurred in four patients, in three of them after venous injuries were ligated. The overall mortality rate was 23%.Our findings show that (1) abbreviated laparotomy reduces mortality in iliac injuries; (2) EABR should be performed early after stabilization to prevent limb ischemia; (3) the use of vascular prostheses with associated intestinal injuries did not appear to increase the incidence of graft infection; and (4) after vein ligation, early fasciotomy and prophylaxis against extremity swelling, deep venous thrombosis, and pulmonary embolism should be considered.

Abstract

To examine the relationship between annual trauma volume per surgeon and years of attending experience with outcome in a Level I trauma center with a large panel of trauma attending surgeons.The outcomes of trauma patients were examined in 1995 and 1996 in relationship to surgeon annual trauma volume and years of experience. Outcome variables studied included overall mortality, mortality stratified by Trauma and Injury Severity Score, mortality in patients with an Injury Severity Score greater than 15, and preventable or possibly preventable deaths. Morbidity outcomes examined were overall complication rate and length of stay per attending surgeon. Additionally, five difficult problems were evaluated for critical management decisions by the attending surgeons, and these outcomes were correlated to annual volume and experience.There was no difference in outcome in either morbidity or mortality that correlated with annual volume of patients treated or years of experience. Critical management errors occurred sporadically and were not related to volume or experience.Outcome after trauma seemed to be related to severity of injury rather than annual volume of cases per surgeon. Although our results may not be applicable to other institutions, they should urge caution in adopting and promulgating volume requirements for individual attending surgeons in trauma centers.

Abstract

Intraoperative blood salvage and autotransfusion are commonly used to minimize exposure to banked blood. Although this technique has been used widely for years, data vary regarding the quality of autotransfused blood. Salvaged blood may contain plasma, residual heparin, and free hemoglobin released from damaged cells. All of these factors may contribute to the adverse sequelae sometimes seen with autotransfusion. For these reasons, we have monitored autotransfused blood to assess its quality. Intraoperative blood salvage was used during most cardiac procedures and at the discretion of the surgeon in other specialties. Blood was collected through a double lumen catheter that was anticoagulated with heparin, filtered, centrifuged, and washed with saline. A sample of the blood was removed for analysis, which included hematocrit, heparin assay, fibrinogen, and free hemoglobin levels. Over a 6-year period, 1593 patients had intraoperative blood salvage with quality assessment. The majority of patients underwent cardiac operations (941 patients, 59%), whereas 243 had orthopedic (15%) and 208 had vascular (13%) procedures. Additionally, there were 127 pediatric patients (8%) and 74 miscellaneous procedures (5%). The highest average yield of salvaged blood was during vascular procedures (1073 +/- 76 mL), whereas orthopedic cases had the lowest yield (378 +/- 19 mL) and hematocrit (39%). There was minimal residual heparin activity, even in patients requiring systemic anticoagulation (0.3 to 0.5 units/mL). Patients undergoing pediatric procedures had the lowest concentration of free hemoglobin (476 mg/L), whereas all adult patients had higher free hemoglobin levels, especially vascular operations (990 mg/L). Intraoperative salvaged blood has minimal heparin activity, even in procedures requiring systemic anticoagulation. Fibrinogen, a marker of residual plasma, was undetectable in the majority of cases. These data indicate that intraoperative blood salvage generally results in a high-quality product (good hematocrit, low heparin, minimal plasma), although there are significant differences in free hemoglobin levels depending on the operative procedure.

Abstract

Intestinal mucosal hypoperfusion and loss of barrier function during sepsis may contribute to maintaining the septic state. Free radicals are produced during sepsis and antioxidants improve survival from experimental sepsis. It is unclear whether endothelial cell injury from free radicals results in altered microvascular reactivity. Lazaroids are antioxidants which scavenge radicals and block lipid radical chain reactions. The authors sought to determine whether lazaroids altered the intestinal microvascular responses to sepsis.In vivo video microscopy was used to study the ileal microcirculation of the rat. A1 (inflow) arteriolar diameter and flow, A3 (premucosal) arteriolar diameters, and cardiac output were measured. Lazaroid or vehicle was infused before a bolus injection of live Escherichia coli or saline.Lazaroid alone had no effect on the intestinal vessels or haemodynamics. E. coli caused vasoconstriction (A1, -21 per cent, A3, -19 per cent of baseline) and hypoperfusion (-36 per cent) despite increased cardiac output (+31 per cent). Lazaroid significantly attenuated both constriction (A1, -11 per cent; A3, 10 to -1 per cent) and hypoperfusion (-15 per cent), but did not increase cardiac output (30 per cent).E. coli bacteraemia led to intestinal vasoconstriction and hypoperfusion. Lazaroid reduced this effect without altering central haemodynamic responses, suggesting that free radicals have a deleterious effect on the intestinal microcirculation during bacteraemia.

Abstract

To assess the role of 12th rib resection in the treatment of postoperative, subphrenic abscesses.Consecutive case series.University hospital, level I trauma center.Operative logs for a 13-year period were reviewed for all patients undergoing 12th rib resection for drainage of a postoperative subphrenic abscess. Each individual medical record was reviewed for demographic data, primary diagnosis, computed tomographic scan findings, and clinical status (temperature, white blood cell count, and Acute, Physiologic, Age, and Chronic Health Evaluation II score) at the time of rib resection.Operative results, microbiological data, complications, and outcomes.Twenty-six patients underwent 27 rib resections for a secondary left subphrenic (23) or a right subhepatic (4) abscess. All patients had undergone at least 1 prior laparotomy (average, 1.5; range, 1-4). Sixteen patients had traumatic injuries, and 7 had complicated pancreatitis. Twelve patients had undergone prior failed attempts at percutaneous drainage before rib resection. Fourteen patients underwent operative drainage without attempted percutaneous drainage, mainly for peripancreatic (7) or multiloculated (3) abscesses. There were 3 postoperative complications (3/27 [11%]): a gastrocutaneous fistula, a gastrocolic-cutaneous fistula requiring laparotomy and temporary colostomy, and fasciitis in the resection site. Four (15%) of the 26 patients died: 3 died of progressive multiple system organ failure, and 1 died of an unrelated injury. The remaining 20 (77%) of the patients were discharged from the hospital with healing wounds and no further episodes of intra-abdominal infection.Twelfth rib resection is an effective alternative therapy for secondary subphrenic abscesses. The nature of the incision allows for open, dependent drainage; avoids subsequent laparotomy; and effectively controls intra-abdominal infections. Twelfth rib resection remains a useful tool in the treatment of subphrenic abscess and may be the preferred approach when other attempts at abscess drainage have failed.

Abstract

Endoscopic percutaneous dilational tracheostomy (PDT) is a good alternative to obtain safe and secure long-term airway control, and is associated with minimal morbidity and mortality.During a 14-month period, we prospectively studied 35 intensive care unit (ICU) trauma patients who underwent early PDT for the sole purpose of obtaining long-term airway control. All patients were determined to need a tracheostomy owing to extubation inability, need to maintain a patent airway, or need for continuous airway access for management of secretions.All patients had sustained multiple injuries with an average Injury Severity Score (ISS) of 29. The time from ICU admission to placement of the PDT was 8 +/- 5 days. The mean Glasgow Coma Scale at the time of the PDT was 10 (range 4 to 15), and 11 patients (31%) had an intracranial pressure device in place. The procedure was completed with bronchoscopic guidance in 33 patients, and in 2 it was converted to surgical tracheostomy (ST). There were no significant complications associated with the placement of the PDT. Two deaths were documented, neither related to the PDT placement. Compared with standard ST, charges were reduced by $1,750.Bedside endoscopic PDT for selected critically ill trauma patients is justified as a safe and effective alternative to ST. The low incidence of complications in PDT suggests that it can be done safely at bedside in the ICU.

Abstract

Percutaneous endoscopic gastrostomy (PEG) is a good alternative that provides long-term nutritional support and is associated with minimal morbidity.During a 24-month period, we studied 54 critically injured patients who underwent early PEG to provide enteral nutritional support. Patients were selected due to the inability to tolerate intake by mouth secondary to multiple associated injuries, especially to the central nervous system.All patients sustained multiple injuries with an average Injury Severity Score of 27. The mean Glasgow Coma Scale at the time of admission was 7 and at the time of the PEG was 10. Eleven patients (20%) had an intracranial pressure (ICP) device, and there was no significant increase in the mean ICP before, during, or after the procedure. In 63% of patients, tube feedings were interrupted for a variety of problems in the 72 h preceding the PEG, and in 70% of patients an average of five radiographs were obtained to document tube position. In 95% of patients, the nutritional goal was achieved within 48 h of PEG placement. There were one immediate and two delayed complications after PEG placement. There were two deaths, neither related to the PEG placement.Early PEG in critically injured patients is a safe and effective method of providing access to the GI tract for nutritional support. In patients with significant brain injuries, adequate sedation and the presence of an ICP monitor help to minimize secondary insults to the brain.

Abstract

Glucose-induced absorptive hyperemia of the intestine has been well demonstrated through microsphere blood flow experiments. We have previously demonstrated that glucose, when applied topically to rat ileal epithelium, restores microvascular vessel diameters and blood flow following Escherichia coli bacteremia or hemorrhage/resuscitation. However, the mechanisms of this hyperemia are not completely understood. We hypothesize that nitric oxide is a mediator of the microvascular response to glucose exposure on the rat intestinal epithelium. Methods: Male Sprague-Dawley rats, 200-225 g, were monitored for hemodynamic stability with mean arterial blood pressure and heart rate. A 2-cm segment of the terminal ileum with intact neurovascular supply was exposed for intravital videomicroscopy. Intestinal arteriolar diameters (A1D, inflow; and A3D, premucosal arterioles) and microvascular blood flow (A1Q) were measured following topical application of isoosmotic glucose or saline, with or without l-NAME (LN, 100 mM), a competitive inhibitor of nitric oxide synthase. Statistical analysis was performed by ANOVA followed by Tukey-Kramer honestly significant difference test. Results: All data are expressed as mean percentage changes from baseline +/- standard error of the mean. Hemodynamic variables did not change during the experimental procedure and there were no significant differences among group baselines. Addition of isotonic glucose to the bath solution caused a significant increase in A3D that persisted throughout the experiment (at 30 min, 19.2 +/- 4.2 vs -3.9 +/- 4.5, P < 0.05). This vasodilation was blocked by topical administration of LN (3.1 +/- 2.9, P < 0.05). A1D remained at baseline levels (saline and glucose) or constricted (LN) in all groups. Topical LN also attenuated A1Q in both the saline and glucose groups. Conclusions: These data demonstrate that glucose-induced intestinal hyperemia is primarily characterized by premucosal A3 arteriole dilation in this model and that nitric oxide is a mediator of glucose-induced intestinal hyperemia. These findings suggest that either (1) glucose directly causes endothelial nitric oxide production or (2) epithelial cells transduce a vasodilatory signal through vascular endothelial-derived nitric oxide during postprandial intestinal hyperemia.

Abstract

Alcohol is a major contributing factor in adult trauma and may adversely affect decision-making in other safety areas such as use of seatbelts and motorcycle helmets. The magnitude of risk-taking behavior and poor decision-making among adolescent trauma patients is not fully appreciated. Our objective was to determine the prevalence and pattern of risk-taking behavior among adolescents (age < or = 20 years) admitted to an adult Level I trauma center.The trauma registry was used to identify patients. Data collected included age, mechanism of injury, blood alcohol and urine toxicology results, seatbelt and helmet use, Glasgow Coma Score, Injury Severity Score, and outcome.Fifteen percent of all admissions to an adult trauma center were adolescents (648 of 4,291). Twenty-one percent of adolescents (138 of 648) and 30% of adults (1,067 of 3,643) tested positive for blood alcohol on admission. Seatbelts were worn by only 19% of adolescent motor vehicle crash admissions versus 30% of adults. Only 7% of adolescents (6 of 83) with detectable alcohol used restraints, compared with 22% (67 of 310) without documented alcohol ingestion (p < 0.05). Adults were somewhat better at restraint use (16% of alcohol-positive patients and 36% without alcohol). Eight of 23 minors (35%) in motorcycle/bicycle crashes were wearing a helmet, compared with 95 of 168 adults (57%). Overall, 6.7% of adolescents and 8.6% of adults had positive toxicology screens. Adolescents with known alcohol consumption were twice as likely to have a positive toxicology screen for illegal drugs (15 vs. 7%; p < 0.05). Alcohol was also frequently detected among adolescents with mechanisms of injury other than motor vehicle and motorcycle crashes, such as violence (25%) and falls (44%).Alcohol is frequently involved in all types of trauma, for adolescents as well as adults. This is often compounded by poor decision-making and multiple risk-taking behaviors.

Abstract

Cyclosporine (CsA)-induced nephrotoxicity may be due to intrarenal vasoconstriction and glomerular hypoperfusion. Several factors, including endothelin and prostanoids, are suggested mediators of this response. Recent evidence suggests that CsA leads to increased oxygen-derived free radical (ODFR) production and lipid peroxidation in renal tissue. Whether this leads to alterations in renal vessel reactivity is unclear. Lazaroids, such as U74389G, are radical-quenching antioxidants that inhibit ODFR-induced lipid peroxidation and may improve renal function after ischemia and reperfusion. We hypothesized that ODFRs contribute to CsA-induced alterations of the renal microcirculation.Rat hydronephrotic kidneys were studied by video microscopy. Interlobular arteriolar diameter and flow, afferent and efferent arteriolar diameters, and cardiac output were measured at 15-min intervals for 120 min. U74389G or its vehicle was infused 15 min before topical application of CsA to the kidney. The results were compared with U74389G alone and normal saline.CsA administration caused renal microvascular vasoconstriction (10-25% below baseline) and hypoperfusion (35% below baseline). Both vasoconstriction and hypoperfusion were significantly attenuated by U74389G (5-8% and 20% below baseline, respectively).Inhibition of lipid peroxidation by U74389G maintained renal blood flow during acute CsA administration. These data suggest that ODFRs are involved in the renal microvascular response to CsA. Inhibition of ODFR-induced lipid peroxidation may help prevent CsA-induced glomerular hypoperfusion. Lazaroids may prove an effective adjunct in reducing CsA-induced nephrotoxicity.

Abstract

Retained hemothorax and infected thoracic collections after trauma can be seen in up to 20% of patients initially treated with tube thoracostomy and have traditionally been treated nonoperatively, often with prolonged hospital stays.Twenty-five patients with retained thoracic collections were reviewed. They underwent 26 thoracoscopies to evacuate undrained blood with or without infection.In 19 patients (76%), the collections were evacuated thoracoscopically. In 4 patients the procedure was converted to an open thoracotomy, and 2 patients required additional procedures to drain these collections. Failure of thoracoscopy correlated with the time between injury and operation and the type of collection, but not with the mechanism of injury. When thoracoscopy was performed in less than 7 days after admission, no cases of empyema were noted at operation.Videothoracoscopy is an accurate, safe, and reliable operative therapy to evacuate retained thoracic collections. In 90% of the patients in whom the procedure was completed, good results were obtained, reducing hospital stay and possible complications. Videothoracoscopy should be the initial treatment in trauma patients with retained thoracic collections and should be used earlier and more frequently in these patients.

Abstract

Blunt popliteal artery trauma is a challenging injury, particularly when associated with major soft tissue damage. We reviewed our experience with this injury to determine 1) the incidence of vascular injury associated with fractures and/or dislocations about the knee, 2) the incidence of limb loss, and 3) factors associated with amputation. We treated 37 patients with 38 blunt popliteal artery injuries and either fractures about the knee or posterior knee dislocations. Patients who underwent primary amputations were excluded. The incidence of popliteal artery injuries with fractures about the knee was 3 per cent, whereas 16 per cent of patients with posterior knee dislocations had vascular injuries (P < 0.05). Amputations were required in 14 of the 38 injured limbs (36%). None of these patients had a pulse or Doppler signal on admission, and 13 had major soft tissue injury. No patient with a pulse or Doppler signal lost a limb (P < 0.05). Limb loss was primarily related to limited venous outflow and/or severe infection in damaged tissue. Failure of the arterial repair rarely led to amputation, particularly in recent years. Two patients with angiographically proven arterial injuries were treated nonoperatively without complications. The incidence of vascular injuries associated with fractures about the knee is low, but somewhat higher with posterior knee dislocations. The overall 9 per cent rate of positive angiograms suggests that a selective approach may be indicated. The amputation rate remains high, but it has improved with an integrated, multidisciplinary team approach. In patients without a pulse or Doppler signal and with severe soft tissue injuries, primary amputation may be appropriate.

Abstract

Deep venous thrombosis (DVT) and pulmonary embolism (PE) are considered to be a major source of morbidity and mortality among trauma patients. Several reports have identified high-risk patients with recommendations for management ranging from frequent duplex scanning to placement of prophylactic inferior vena cava (IVC) filters. We reviewed our experience with a large trauma population to determine whether such approaches are justified.We analyzed 2,868 consecutive trauma admissions over 22 months and identified 280 patients (10%) in high-risk groups who survived > or = 48 hours: (1) severe closed head injury with mechanical ventilation > or = 72 hours, (2) closed head injury with lower extremity fractures, (3) spinal column/cord injury, (4) combined pelvic and lower extremity fractures, and (5) major infrarenal venous injuries. The remaining nonthermal injury patients constituted the low-risk group.There were 280 high-risk patients, 213 of whom (76%) received prophylaxis with compression therapy. There were 12 cases of DVT (5%) with four nonfatal PE (1.4%). Six patients (2%) had therapeutic IVC filters inserted and only one patient had prophylactic placement. There were 38 deaths in this group, attributable primarily to severe closed head injury or spine injuries, and none were caused by PE. In the 2,249 low-risk patients, there were three cases of DVT (0.1%, p < 0.05 vs. high risk) and no PE (p < 0.05 vs. high risk).Although these patients were at increased risk for thromboembolic events, the overall incidence of DVT was still extremely low with no apparent PE deaths. In our patient population, aggressive screening and prophylactic IVC filters would not have benefited 95% of "high-risk" patients without DVT and would not have prevented any deaths. We could not identify any population, except perhaps venous injuries, where such expensive and potentially harmful maneuvers seemed justified. Our experience with DVT and PE does not support either aggressive screening or prophylactic IVC filters as the standards of care.

Abstract

Altered vascular responsiveness is the hallmark of septic shock. Recently, these changes have frequently been attributed to increased production of nitric oxide (NO). Continued exposure to high levels of NO may alter both endothelial and vascular smooth muscle cell function. Although ex vivo studies demonstrate hyporeactivity of large conduit arteries during established sepsis, it is unclear if the same phenomena exist during early sepsis. This is especially true in the small resistance arterioles of the viscera. We used in vivo microscopy of the rat small intestine to assess (1) endothelial-dependent relaxation and vasomotion (periodic contraction and relaxation of blood vessels) in response to acetylcholine (ACH; 10(-8) to 10(-5) M), (2) endothelial-independent relaxation to nitroprusside (NTP; 10(-5) M), and (3) vascular smooth muscle response to norepinephrine (NE; 10(-10) to 10(-7) M) in normal and bacteremic rats (Escherichia coli). There were no alterations in endothelial-dependent or -independent relaxation during bacteremia as measured by mean diameters. However, acute E. coli bacteremia severely impaired vasomotion in A1 (inflow) and A3 (premucosal) arterioles. Vasomotion was returned to baseline levels in A1 with low-dose ACH (10(-8) M) but only partially improved in A3 arterioles (P < 0.05). A1 response to NE was impaired, while A3 were minimally altered despite being more sensitive to E. coli-induced vasoconstriction. These data suggest that bacteremia causes a rapid, differential impairment of both endothelial-dependent (A3 vasomotion) and vascular smooth muscle cell (A1 constriction) functions. These microvascular impairments occur much earlier than previously described and may contribute to sepsis-induced mucosal ischemia of the intestines.

Abstract

Multiple system organ failure (MOF) remains a major source of morbidity and mortality in trauma patients. Despite restoration of central hemodynamics, intestinal hypoperfusion can persist. Mucosal ischemia and barrier breakdown are factors in the genesis of MOF. Heparan sulfate is a gycosaminoglycan similar to heparin, but with minimal anticoagulant properties. As an adjunct to resuscitation, it improves immunologic function and restores mucosal oxygenation and function. We hypothesized that resuscitation with heparan following hemorrhage wound prevents intestinal hypoperfusion.In vivo videomicroscopy was used to study small intestine microcirculation in rats. Animals were hemorrhaged to 50% of baseline mean arterial pressure (MAP) and maintained there. Resuscitation was initiated when the return of 10% shed blood was required to keep MAP at 50%. Animals received either heparan (7 mg/kg/1 ml saline) or saline (1 ml) followed by the remaining shed blood and an equal volume of saline. MAP, cardiac output (CO), A1 arteriole diameters, and flow were determined.Resuscitation of the saline control group resulted in normal MAP with elevation of CO to 25-40% above baseline. The heparan group had return of MAP but only a moderate increase in CO (7-15%). Saline resuscitation led to progressive deterioration in A1 diameters and flow. The addition of heparan prevented delayed A1 constriction and significantly improved perfusion.Heparan prior to resuscitation improved intestinal perfusion, despite a relative reduction in CO. Improvement in nutrient blood flow may protect the mucosal barrier, reducing the incidence of MOF, and suggests that heparan may be useful in resuscitation of trauma patients.

Abstract

Although management of penetrating abdominal trauma has greatly improved, abdominal aortic gunshot wounds (AAGSWs) remain a highly lethal injury. Our experience with AAGSWs was reviewed to define operative strategies that may improve survival.Forty-one patients with AAGSWs were treated between 1976 and 1996. Preliminary thoractomy was performed in seven patients. Thirty-nine patients had at least one major associated injury (average, 3.2).Twenty-one patients died. Six of seven patients who underwent preliminary thoracotomy died; all developed coagulopathy, which appeared to contribute to death. Four patients had missed vascular lesions, two of which contributed to their death. Associated injuries are currently managed by "damage control" strategy, in which some injuries are left untreated to focus on hemorrhage control.We have identified seven operative principles and procedures that we believe may improve survival: (1) thorough knowledge of supraceliac exposure; (2) rapid aortic control at the hiatus rather than by a preliminary thoracotomy; (3) use damage control or abbreviated laparotomy; (4) use packing and mesh closure when coagulopathy and hypothermia are present; (5) primary concern should be cessation of hemorrhage rather than the maintenance of flow; (6) delayed reconstruction using extraanatomic bypass can restore flow; and (7) use angiography to detect missed vascular lesions or problems with vascular repair.

Abstract

Acute kidney failure in surgical patients is often related to severe infection. Renal vasoconstriction is a major factor in the genesis of kidney failure. Reactive oxygen species (ROS) are known to mediate kidney injury after ischemia-reperfusion and are increased during sepsis. The role of ROS as mediators of intrarenal vasoconstriction and renal dysfunction during sepsis is unclear. Lazaroids such as U74389G are radical quenching antioxidants that inhibit ROS-induced lipid peroxidation. We sought to determine whether radical scavenging affected the renal microvascular response to a septic challenge.In vivo videomicroscopy was used to study the rat hydronephrotic kidney. Interlobular artery (ILA) diameter and flow, afferent and efferent arteriolar diameters, and cardiac output were measured. U74389G or vehicle was infused before a bolus injection of live Escherichia coli or normal saline solution.U74389G alone had no effect on the renal vessels or hemodynamics. E. coli caused preglomerular vasoconstriction (ILA, -32%; afferent, -30% of baseline) and hypoperfusion (-66%) despite increased cardiac output (+54%). U74389G significantly attenuated both the constriction (ILA, -16%; afferent, -9%) and hypoperfusion (-38%) but not increased cardiac output (+41%).E. coli bacteremia led to preglomerular vasoconstriction and hypoperfusion. Inhibition of lipid peroxidation with the radical scavenger U74389G reduced this effect without altering central hemodynamic responses. Free radicals have a deleterious effect on the renal microcirculation during bacteremia, and these data suggest that antioxidants may be of value in preventing sepsis-associated kidney failure.

Abstract

To study the hypothesis that fluid resuscitation alters cytokine gene expression after experimental murine peritonitis.Mice underwent cecal ligation and puncture (CLP) to induce peritonitis and were randomized to receive variable amounts of normal saline (0, 0.25, 1.0 ml. subcutaneously) and serum (0 or 0.1 mL) after operation. Hepatic and small intestinal (ileal) tissue were harvested at 3 or 6 hours after CLP, and total tissue RNA was extracted. Reverse transcriptase polymerase chain reaction was used to provide relative quantitation of tumor necrosis factor-alpha and interleukin (IL)-1 beta messenger RNA (mRNA) compared with beta-actin.CLP without resuscitation resulted in significant increases in hepatic tumor necrosis factor-alpha mRNA (1190% at 6 hours compared with normal animals), and IL-1 beta mRNA (1475%), and intestinal IL-1 beta mRNA (1243%). Volume administration attenuated cytokine expression at both 3 and 6 hours, and saline seemed to have more potent effects than serum. The volume of resuscitation correlated with survival at 18 hours. Survival in the saline (1 mL) + serum group was 90% at 18 hours compared with 20 to 40% in the groups with little or no resuscitation. Overall, there were no survivors at 30 hours.Fluid resuscitation (amount, composition, timing) should be an important consideration in the utilization of experimental infection models. Furthermore, optimization of the patient's intravascular volume status during sepsis may have important effects on immune responses, in addition to improving hemodynamic variables.

Abstract

Complex thoracic injuries are a leading cause of death in trauma patients. Four difficult problems of diagnosis and treatment are discussed, including (1) air leak not associated with pneumothorax, (2) management of major thoracic esophageal injuries, (3) penetrating trauma, and (4) retained hemothorax and empyema.

Abstract

Bacteremia leads to rapid intrarenal vasoconstriction, mediated by endogenous vasoconstrictors such as TXA2 and endothelin. These changes occur before the onset of neutrophil adherence, platelet aggregation, or increases in proinflammatory cytokines. Pentoxifylline (PTX) increases red cell deformability, reduces neutrophil adhesion, abrogates rises in TNFalpha, and lessens the deleterious effects of other cytokines during prolonged sepsis. PTX also improves renal function in models of established sepsis, but the specific mechanisms of this effect are unclear. Because PTX is a relatively selective visceral vasodilator we sought to determine whether PTX improves renal microvascular hypoperfusion during bacteremia and whether the mechanism involves altered vascular reactivity. Rat hydronephrotic kidneys were studied by videomicroscopy. Interlobular (ILA) arteriolar diameter and flow, afferent (AFF) and efferent (EFF) arteriolar diameters, and cardiac output (CO) were measured at 15-min intervals for 120 min. PTX was infused alone or prior to a bolus injection of live Escherichia coli. The responses were compared to controls infused with equivalent volumes of normal saline alone. PTX led to improved renal blood flow and to pre- and postglomerular vasodilatation. This improvement remained significant compared to bacteremic animals throughout the period of observation. We conclude that PTX improves renal blood flow during bacteremia due to pre- and postglomerular vasodilation. These responses may be a consequence of increased intracellular cAMP and release of vasodilator prostanoids.

Abstract

To determine if the decision to pack for hemorrhage could be refined.Seventy consecutive trauma patients for whom packing was used to control hemorrhage were studied. The patients had liver injuries, abdominal vascular injuries, and bleeding retroperitoneal hematomas. Preoperative variables were analyzed and survivors compared with nonsurvivors.Packing controlled hemorrhage in 37 (53%) patients. Significant differences (p < 0.05) between survivors and nonsurvivors were Injury Severity Score (29 vs. 38), initial pH (7.3 vs. 7.1), platelet count (229,000 vs. 179,000/mm3), prothrombin time (14 vs. 22 seconds), partial thromboplastin time (42 vs. 69 seconds), and duration of hypotension (50 vs. 90 minutes). Nonsurvivors received 20 units of packed red blood cells before packing compared to 13 units for survivors.Patients who suffer severe injury, hypothermia, refractory hypotension, coagulopathy, and acidosis need early packing if they are to survive. Failure to control hemorrhage is related to severity of injury and delay in the use of pack tamponade. A specific protocol that mandates packing when parameters reach a critical limit should be considered.

Abstract

Patients with multiple system disease undergoing elective noncardiac surgical procedures are at variable risk for developing postoperative complications and death. To determine whether preoperative expansion of plasma volume would improve outcome, 306 patients were admitted to the Surgical Intensive Care Unit of the Veterans Administration Center for Swan-Ganz catheter placement and measurement of hemodynamic responses to a 2 L infusion of normal saline over 2 hours. Intraoperative stability and postoperative outcome were assessed by chart review and compared with similar operative groups of patients who did not receive saline infusion. Eighty-eight per cent of the patients had a positive expansion of blood volume with saline infusion. In patients undergoing aortic reconstructive procedures, there was a reduction in the incidence of postoperative complications (52% to 28%) primarily attributed to a reduction in pulmonary complications. In all patients there was an improvement in intraoperative cardiovascular stability (57% saline vs 38% control), a reduction in the need for pharmacologic support of blood pressure (19% saline vs 30% control), and reduction in the amount of intraoperative fluid administration (hydration index: 5.12 saline vs 8.61 control). We therefore conclude that preoperative saline loading is associated with improved outcome in high risk elderly patients undergoing elective, noncardiac surgical procedures.

Abstract

Endothelins (ET) have been demonstrated to mediate intestinal microvascular constriction during acute Escherichia coli bacteremia, however, their role during chronic infection is unknown. The purpose of this study was to determine whether ET-1 is synthesized in the small intestine in a more chronic peritonitis model. ET-1 mRNA levels of the terminal ileum in mice following cecal ligation and puncture (CLP) were compared to sham-operated animals and normal unoperated animals. ET gene expression was analyzed using differential reverse transcriptase chain reaction (RT-PCR) with co-amplification of beta-actin as an internal standard. To assess ET peptide expression, serum and intestinal tissue levels were measured using a specific enzyme immunoassay (ELISA). The pattern of ET-1 gene expression post-CLP with a single puncture of the cecum with a 23 ga. needle demonstrated a 3.6-fold increase at 8 h, and a return to sham levels by 24 h (374 +/- 64% at 8 h, p < .05, 128 +/- 13%). An increase of mRNA levels at 24 h post-CLP was observed with a double puncture with an 18 ga. needle (230 +/- 36%, p < .05) accompanied by an increase in serum ET levels (270 +/- 31%, p < .05) and higher tissue ET levels. These data indicate a time-dependent response of ET-1 gene expression in the terminal ileum post-CLP which is related to severity of infection.

Abstract

Early enteral nutrition is reported to improve outcome of patients with severe closed head injuries (CHI). The efficacy and safety of nasoenteric tube (NET) feeds, however, has been questioned; the risk of aspiration is the major concern. Our purpose was to determine the rate of transpyloric migration, the efficacy of adjunctive measures to promote passage, and the effect on pulmonary complications. Seventy-four consecutive patients with moderate to severe CHI received enteral nutrition. Glasgow Coma Scale (GSC) score was 5.2 on admission and 6.9 at 48 hours. NETs were placed an average of 5.6 days after admission; an average of three abdominal films per patient were used to assess tube position. No patients had endoscopic NET placement during this period. Ten patients required fluoroscopic placement after failure to pass spontaneously by 5 days. Overall, transpyloric passage was achieved in 32 patients (43%), whereas 42 (57%) remained intragastric. There were no differences between the postpyloric and intragastric groups in days to full feeding (5 vs. 7 days), ventilator days (11.9 vs. 12.5), intensive care unit length of stay (15.5 vs. 15.1), or incidence of pneumonia (81 vs. 69%) or aspiration (6 vs 7%). Sixty-two patients (83%) were transferred to extended care facilities and 50 (68%) were still receiving NET feedings. Spontaneous transpyloric passage of NET occurred in less than one-half of patients with severe CHI. The routine use of adjunctive measures to promote transpyloric passage was not particularly successful, had no obvious benefit, and therefore may not be necessary.

Abstract

Haemophilus species are a common cause of community-acquired pneumonia; however, their significance in posttraumatic pneumonia is unclear.Case series.University hospital, level I trauma center.Two hundred fifty-seven consecutive patients with blunt and penetrating trauma treated for pneumonia.Length of stay in the intensive care unit, duration of ventilatory support, rate of recurrent or persistent pneumonia, and mortality.Ninety-six (37%) of 257 patients treated for pneumonia had a Haemophilus species isolated on sputum culture. Of these 96 patients, 49 (51%) had only Haemophilus species, while 33 (34%) had associated gram-positive organisms and 14 (15%) had gram-negative organisms. Seventeen pure cultures (29%) and seven mixed cultures (15%) (P < .05) were beta-lactamase-positive trains. Compared with patients who had pneumonia caused by other bacteria, patients with Haemophilus species were younger (mean +/- SE, 35 +/- 1.7 vs 42 +/- 1.6 years; P < .05) and more severely injured (Injury Severity Score, 20.7 +/- 1.1 vs 17.5 +/- 0.9; P < .05). There were no differences in any outcome variables between the two groups. Only one (1%) of 96 patients had persistent Haemophilus species on sputum cultures after 7 days of treatment.Haemophilus species are a frequent cause of pneumonia following traumatic injury. This occurs primarily in the early postinjury phase and therefore should be included in the differential diagnosis of early posttraumatic pulmonary insufficiency.

Abstract

The effect of timing of femur fracture fixation for patients with multiple trauma was studied to determine the effect of operative timing on eventual outcome.The relationship between timing of intramedullary rod (IMR) placement, degree of injury, and pulmonary complications was studied in 424 consecutive patients. The authors focused on 105 patients undergoing IMR placement with an Injury Severity score (ISS) of greater than or equal to 18. The effects of timing of IMR placement on various pulmonary complications, organ failure, intensive care unit (ICU) admission, and ventilatory assistance were studied for various time intervals.Of the 424 patients, pulmonary complications increased slightly in the more seriously injured group (ISS > 18) but were not influenced by the timing of IMR placement. Of the 105 patients undergoing IMR placement with an ISS > or = 18, only 2 patients died. Both patients had an IMR placed in less than 24 hours and died later of head injury and delayed hemorrhage. The incidence of organ failure, number of ventilator days, and length of ICU stay did not differ between the groups based on timing of fracture fixation. The incidence of severe head injuries was higher in the group undergoing delayed IMR placement (> 48 hours).Modest delays in IMR placement did not adversely affect patient outcome. Pulmonary complications were related to the severity of injury rather than to timing of fracture fixation. In a well-integrated trauma system, clinical judgment regarding the timing of IMR placement was the most important determinant of outcome. Delays that were made to stabilize the patient, treat associated injuries, and plan orthopedic reconstruction did not adversely affect patient outcome.

Abstract

Resuscitation (RES) after hemorrhage (HEM) results in persistent arteriolar constriction and hypoperfusion of the small intestine (SI) despite restoration of mean arterial pressure (MAP) and cardiac output (CO) to normal values. We postulated that increased adrenergic activity contributes to this vasoconstriction and impairment of flow. A loop of SI from decerebrate rats was exteriorized and suffused with Krebs' solution (37 degrees C, pH 7.4). In initial experiments, the effectiveness of alpha-adrenergic receptor antagonism by phentolamine (PHEN) was assessed. Subsequent groups received either topical PHEN (10(-6) M, n = 6) or saline (n = 6) in the suffusion and were then bled to 50% baseline (BL) MAP for 60 min and resuscitated to BL with shed blood/lactated Ringer's. Intravital microscopy and optical Doppler velocimetry were used to measure large (A1) and small, premucosal (A3) arteriolar diameters and RBC velocity; microvascular blood flow was calculated. MAP and transpulmonary CO were measured. During HEM, control animals developed A1 constriction and hypoperfusion with A3 arteriolar dilation. PHEN treatment prevented A1 constriction and enhanced A3 dilation but did not improve flow. Immediately after RES in controls, microvascular diameters and A1 flow returned to BL; however, over the 2-hr post-RES period there was progressive A1 and A3 vasoconstriction and hypoperfusion despite maintenance of BL MAP and CO. After RES in PHEN-treated animals, A1 flow returned to BL, but progressive hypoperfusion was only partially prevented. alpha-Adrenergic-mediated vasoconstriction contributes to intestinal hypoperfusion after HEM, but other mechanisms are also involved in microvascular responses during RES.(ABSTRACT TRUNCATED AT 250 WORDS)

Abstract

The normal or hyperdynamic circulatory response during the early phases of the systemic septic response is associated with renal microvascular constriction and can result in renal dysfunction. Intrarenal redistribution of blood flow from the outer cortex to the medulla appears to account for decreased glomerular filtration in spite of normal or elevated renal blood flow, but the mechanisms of this response are not well described. Nitric oxide is recognized as an important regulator of regional blood flow during both normal and pathologic conditions including sepsis, and we hypothesized that alterations in nitric oxide contribute to redistribution of renal blood flow during sepsis. The current study used laser Doppler fluximetry and clearance of p-aminohippuric acid (effective renal plasma flow, ERPF) to study intrarenal distribution of blood flow during basal conditions and during normodynamic Escherichia coli bacteremia, with and without inhibition of nitric oxide. Inhibition of nitric oxide in normal animals resulted in a decrease in ERPF (-19%) with a decrease in cortical flux (-39%) without alteration of medullary flux. Bacteremia resulted in a decrease in cortical flow (-17%), an increase in medullary flow (36%), and a modest reduction (-9%) in ERPF. Inhibition of nitric oxide synthase during bacteremia worsened cortical flow (-43%), reversed the increase in medullary flux (-42%), and further impaired ERPF (-28%). These data suggest that nitric oxide regulates renovascular tone during normal conditions and bacteremia, and indicate that it is a prime mediator of intrarenal redistribution of blood flow during sepsis.

Abstract

Nephrotoxicity caused by cyclosporin A (CSA) is the result of vasoconstriction of the renal microcirculation. The endothelium-derived relaxing factor nitric oxide (NO) regulates microvascular blood flow in various tissues, and mediates the microcirculatory response during hypertension and sepsis. This study investigated the role of NO in CSA-induced renal vasoconstriction. Hydronephrotic kidneys in rats were suspended in an environmentally controlled tissue bath, and interlobular, afferent and efferent arteriolar diameters and blood flow were measured by in vivo videomicroscopy. CSA was administered alone, with the nitric oxide synthase (NOS) inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) or with exogenous NOS substrate L-arginine. CSA significantly constricted the whole of the renal microvasculature whereas L-NAME alone preferentially constricted the preglomerular vessels. L-Arginine reversed the vasoconstriction induced by CSA whereas L-NAME had no further effect. Preglomerular basal vascular tone is dependent on continuous production of NO and alterations in the L-arginine-NO pathway contribute to CSA-induced renal vasoconstriction.

Abstract

Platelet-activating factor (PAF) and bacteremia both cause small intestinal (SI) hypoperfusion which may contribute to mucosal injury, and PAF has been postulated to mediate impaired SI microvascular blood flow during sepsis. Our previous studies demonstrate that sepsis-induced SI hypoperfusion is associated with both arteriolar and venular constriction, but the microvascular mechanisms by which PAF impairs SI blood flow are not well defined. Microcirculation studies in other tissues indicate that PAF is an arteriolar dilator, but this effect in the SI would not explain PAF-mediated hypoperfusion. We studied the effects of PAF on SI microvessels to characterize the microvascular mechanisms which mediate PAF-induced hypoperfusion. We also determined the role of PAF as a mediator of microvascular effects in the intestine during bacteremia by PAF receptor antagonism. Animals received either 10(9) live Escherichia coli IV or PAF applied topically to the SI (30, 80, and 300 nM). Arteriolar and venular diameters and red blood cell velocity (A1, V1) were measured with intravital microscopy and velocimetry. Both PAF and sepsis resulted in impaired SI blood flow (maximum decrease in blood flow -37 and 65%, respectively), but sepsis was associated with both arteriolar and venular constriction (20 and 30% diameter reduction each), whereas PAF produced only venular constriction (50% diameter reduction). Inhibition of PAF action prevented the microvascular alterations of bacteremia (blood flow unchanged, P < 0.05; venular diameter unchanged, P < 0.05), suggesting that PAF is an important mediator of these responses.

Abstract

To determine whether arachidonic acid metabolites are mediators of regional blood flow changes during sepsis, we examined the effects of cyclooxygenase blockade on intestinal microvascular diameters and blood flow during acute bacteremia, induced in the rat by the intravenous injection of 10(9) live Escherichia coli. Mean arterial pressure, cardiac output, intestinal microvascular diameters, and blood flow were measured in the presence or absence of a topically applied selective cyclooxygenase inhibitor (mefenamate). Bacteremia caused a diffuse constriction of both arterioles and venules and a concomitant 50% decrease in blood flow. Treatment with mefenamate did not affect baseline intestinal microvascular tone or bacteremia-induced arteriolar constriction and hypoperfusion, but did reverse an intense venular constriction. Our results suggest that the small intestinal microcirculation has a differential response to cyclooxygenase products of arachidonic acid metabolism during acute bacteremia. They appear not to be mediators of the intestinal arteriolar constriction and hypoperfusion observed during acute E. coli bacteremia, but profoundly influence the mesenteric venular constriction. These observations support the concept that microvascular control mechanisms are different not only between but within organ specific vascular beds.

Abstract

Antibiotic usage was assessed in a prospective, randomized trial of recombinant interferon-gamma (rIFN-gamma) versus placebo for 212 severely injured trauma patients in four university hospitals. All patients were observed until death or discharge from the hospital. We found the number of antibiotics used and their associated costs staggering and difficult to justify, although serious antibiotic-related complications were infrequent. Regular antibiotic administration following severe trauma should be re-evaluated since clinical evidence supports the use of shorter courses for these patients, with presumed similar outcomes and much-reduced expenses.

Abstract

Hyperdynamic sepsis is often complicated by renal dysfunction, caused in part by renal vasoconstriction and impaired blood flow. Nitric oxide (NO) is an important mediator of hemodynamic responses to sepsis; however, its importance in the renal microcirculation during sepsis is unknown. Our purpose was to determine the role of NO in the renal microcirculation during bacteremia.In vivo videomicroscopy was used to study the microcirculation in five groups of hydronephrotic rat kidneys. Cardiac output (CO), mean arterial pressure, interlobular artery (ILA) diameter and flow, and afferent (AFF) and efferent arteriole diameters were measured.NO synthase inhibition in normal rats resulted in hypertension, decreased CO, selective preglomerular constriction (ILA, -21%; AFF, -26% of baseline), and hypoperfusion (-56%). Escherichia coli resulted in a normotensive, high CO state (+23%) with ILA (-25%) and AFF (-20%) constriction and hypoperfusion (-60%). NO synthase inhibition during bacteremia normalized CO and increased mean arterial pressure (+34%) but exacerbated constriction (ILA, -45%; AFF, -33%) and further impaired flow (-90%).NO maintains preglomerular tone and flow during basal conditions and appears to counteract intrarenal vasoconstrictors during E. coli bacteremia.

Abstract

Forty-three trauma patients underwent tracheostomy (TRACH) and percutaneous endoscopic gastrostomy (PEG) over 21 months. Thirty-one patients had a head injury with Abbreviated Injury Scale > or = 3 associated with multi-trauma. This study was undertaken to analyze demographic and outcome variables with respect to timing of TRACH/PEG in this population. Patients were divided into EARLY (< or = 7 days) and LATE (> 7 days) groups and were analyzed for admission Glasgow Coma Scale, Apache II, Injury Severity Score, and [(A-a)DO2] at time of TRACH/PEG. Outcome variables were ICU length of stay (LOS), hospital LOS, days of mechanical ventilation (MV) post-TRACH/PEG, complications, and mortality. Esophagogastroduodenoscopy findings with PEG and days to full enteral nutrition were recorded. All demographic variables were statistically similar between the EARLY and LATE groups. The EARLY group had shorter hospital LOS (P < 0.05), total Intensive Care Unit LOS (P < 0.05), ICU LOS post-TRACH/PEG (P < 0.05), and fewer days of MV post-TRACH/PEG (P < 0.05). There were no procedure-related complications of TRACH/PEG in either group. Full Esophagogastroduodenoscopy performed at the time of PEG had a high diagnostic yield in both groups. We conclude that TRACH/PEG performed within the first 7 days of injury in the head trauma patient is the procedure of choice for long-term airway protection, mechanical ventilation, and enteral nutrition. Combined use of these procedures reduces ICU and hospital LOS and shortens the course of MV.

Abstract

The records of 26 patients who underwent cholecystostomy procedures for presumed acute cholecystitis during a 6-year period were reviewed. Nine patients had operative tube cholecystostomy (OC), and 17 patients had radiologic percutaneous cholecystostomy (PC). A correct diagnosis of acute cholecystitis was made in 22 of 26 patients (84%), including 14 of 17 PC patients and 8 of 9 in the OC group. The rate of resolution of cholecystitis was the same in each group (75% OC versus 78% PC). APACHE II scores prior to treatment were significantly higher in OC patients (20.9 OC versus 12.4 PC, p < 0.01). There were 5 deaths, including 3 in the OC groups and 2 in the PC group. Nonfatal complications were more frequent in the PC group. Two of the 14 correctly diagnosed PC patients (14%) subsequently required emergency cholecystectomy for persistent biliary sepsis, and 6 patients (43%) required at least 1 tube exchange for occlusion or dislodgement. Overall, only 5 of the 14 patients (36%) in the PC group were successfully treated without complications compared with 5 of 8 patients (63%) in the OC group. Despite its theoretical advantages, PC was no more effective than OC in the treatment of acute cholecystitis. These data suggest that OC remains a viable treatment option in critically ill patients with acute cholecystitis.

Abstract

The intestinal sling procedure has been used successfully without the observance of pelvic infections. This procedure involves the implantation of polyglycolic acid (PGA) mesh to hold the bowel out of the pelvis to prevent radiation enteritis. We previously showed that PGA mesh has no intrinsic bactericidal activity. Since phagocytic leukocytes produce reactive oxygen intermediates during respiratory burst that are associated with oxygen-dependent bactericidal activity, we examined peritoneal cell types and their respiratory burst activity isolated from patients with biopsy-confirmed rectal carcinoma who underwent the intestinal sling procedure (N = 12) compared with patients who did not (N = 13). There was no significant difference in the cell types within the peritoneal cavity over the 7-day postoperative period examined. However, there was a significant increase in the ability of leukocytes isolated from mesh patients to produce hydrogen peroxide in the absence of an exogenous stimulus (P less than 0.05), as measured by flow cytometric quantitation of oxidation of the hydroperoxide-sensitive dye, 2',7'-dichlorofluorescin diacetate (DCFH-DA). Despite the higher endogenous DCFH oxidation by leukocytes from mesh patients, the cells retained the ability to oxidize DCFH following treatment with a membrane-active stimulant for respiratory burst activity, 12-O-tetradecanoyl-phorbol-13-acetate. These observations suggest that PGA mesh used for the intestinal sling procedure stimulates the respiratory burst activity of peritoneal leukocytes during the postoperative period in which bacterial proliferation and colonization occur. The stimulation of reactive oxygen intermediates involved in oxygen-dependent bactericidal activity by PGA mesh may be one of the mechanisms underlying the lack of infections observed with the use of PGA mesh in contaminated settings.

Abstract

Portable resuscitation-area cervical-spine radiographs (PCS) frequently constitute a routine part of the emergency evaluation of patients suffering from blunt trauma. Their adequacy and cost were evaluated by reviewing the records of 92 consecutive trauma patients. Forty-seven of 74 patients (63.5%) had adequate PCS in that all seven cervical vertebrae were visualized. In 27 patients (36.5), all seven cervical vertebrae were not adequately visualized. Inadequate studies were most likely to occur in patients with abnormal vital signs on admission (56%) (P less than .01) and in those subsequently requiring general anesthesia (34.5%). Fifteen patients were intubated without difficulty by maintaining neck immobilization because of uncertainty regarding cervical-spine injuries. The annual cost of inadequate cervical-spine studies was estimated to be $31,000.00. Although the four cervical-spine injuries were diagnosed by the portable technique, routine PCS were frequently inadequate in visualizing all seven cervical vertebrae. Major decisions concerning intubation and surgery frequently had to be made before adequate radiographic evaluation could be completed. It is suggested that time and money are lost by routinely doing a single lateral portable cervical radiograph. It is more appropriate to obtain complete radiographic studies after life-threatening injuries are addressed while patients are treated using the standard techniques of neck immobilization.

Abstract

The Whipple procedure traditionally is associated with an operative mortality of 20 to 25 percent. As a result, percutaneous and endoscopic techniques have been advocated to alleviate symptoms in patients with periampullary carcinoma. Now, dramatic reductions in operative mortality rates have been reported. Since radical pancreaticoduodenectomy is the only treatment for cure, a re-evaluation of the role of this procedure is warranted.